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Series Nout 


“SOME SOLITARY WASPS 
OF TEXAS" 


ILLUSTRATED WITH ORIGINAL PHOTOGRAPHS | 
TAKEN IN THE FIELD. 


BY 


CARL HARTMAN? 


oe “*Read before the Texas Academy of Science, June 8, 1904 . 
_*Oontrtbution from the Zoological Laboratory of the University of ba No. 67 


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BULLETIN OF THE UNIVERSITY OF TEXAS 
No. 65. 
2 ISSUED SEMI-MONTHLY 
Scientific Series No, 6 July 1, 1905 


OBSERVATIONS ON THE HABITS OF 
SOME SOLITARY WASPS 
OF TEXAS* 


ILLUSTRATED WITH ORIGINAL PHOTOGRAPHS 
TAKEN IN THE FIELD. 


BY 


CARL HARTMAN? 


*Read before the Texas Academy of Science, June 8, 1904 
10ontribution from the Zoological Laboratory of the University of Texas, No. 67 


PUBLISHED BY 


THE UNIVERSITY OF TEXAS 


Entered as second-class mail matter at the postoffice at Austin, Texas 


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DEC 29 1987 Gof 


———— 


INTRODUCTION. 


On morphological grounds wasps may be divided into two main 
groups, the Sphecina or digger-wasps, and the Vespina or true 
wasps, the latter of which have their wings folded in plaits when 
at rest. (Compare Figs. 1 and 2.) For the purpose of this paper, 
which is a study on habit, wasps may best be divided into the 
social and the solitary. This classification, based on habit, does 
not coincide with that based on the condition of the wings, for 
while the Sphecina are all solitary, the Vespina also include a large 
group of solitary wasps, the Eumenidae. 

To render my account more complete, I shall briefly compare 
the habits of the social and the solitary wasps, transcribing from 
others. 

A social community includes three castes: queens, drones, and 
workers. The queens alone survive the winter after mating with 
the drones, which, with the workers, perish of hunger and cold. 
In the spring the queen builds the first comb and rears the first 
lot of workers. These immediately take up the work of building 
the nest and feeding the young, while the queen devotes herself 
exclusively to egg-laying. Before long, many hundreds of workers 
are busy in the nest, and, late in the season, many queens and 
drones also appear, and the cycle of life is started anew. 

The solitary wasps have only two sexes, the queens and the 
drones, and there is no division of labor, though some genera 
(Pelopaeus, Bembex and Microbembex) build their individual nests 
close together, forming colonies. There is a great diversity of 
habits both among the Eumenide and the Sphecina. In either 
group the nests may be made of mud and attached, for shelter, 
under rocks, the eaves of buildings, or the hollows of trees, or 
they may be attached to the stems of plants. The nest may be 
tubes in the stems of plants, in boards.or in the ground, either 
found ready made, or, as is usual, newly bored or dug by the 
individual wasps using them. 

The adult wasps live on the nectar of flowers or on animal food, 
namely the same insect prey which they give their offspring. This 
usually consists in a given species of wasps of a particular kind 
of insect, one capturing only caterpillars, others only spiders, flies, 
bugs, beetles or other insects as the case may be. 


4 Some Solitary Wasps of Tezas. 


The solitary wasps mate in the spring or summer. The female 
alone engages in the work of rearing the family. When the egg- 
laying time arrives, she digs or builds a nest, secures her prey, which 
she either kills outright or merely paralyzes, stores it in her nest 
and lays her eggs among the store of provisions. In most cases, 
the food is carried home once for all, the nest is closed over the egg 
and the mother flies away and digs a nest in another place, paying 
no further attention. to, the old nest. In a few genera, the mother 
maintains a further connection with her offspring, feeding the 
growing larva from day to day until it has spun its cocoon. 

The egg of a solitary wasp hatches in one to three days into a 
maggot-like larva, which feeds on its store of provisions and grows 
for two weeks or less, when it spins its cocoon and becomes a pupa. 
In this state it remains two or three weeks in summer before 
emerging as the perfect insect; or if cold weather comes on, the 
insect remains quiescent in the pupal state until the following 
spring. It is probable that no adult solitary wasp survives the 
winter, 

The solitary wasp emerges from its cocoon in possession of all 
the instincts of its ancestors. It is, moreover, born into the world 
alone, and there is no chance for imitation of its fellows, as is the 
case with social bees and wasps. Wonderful as these instincts are, 
they are not so perfect as was supposed, for observation has shown 
that they are to a high degree variable, and often show remarkable 
adaptation to circumstances, which is called by some, intelligence. 
The study of the habits of animals had been too little studied to 
bring out the fact of variability, for it is apparent that, to detect 
variations, be they in morphological characters or in actions, the 
type of structure or the normal action of the animals must first 
be determined. The present paper is a contribution in this direc- 
tion, as it embodies observations of some twenty-eight species of 
Texas solitary wasps. 

The principal students of the habits of solitary wasps, in fact, 
the only ones that have studied them comparatively, are M. J. H. 
Fabre of France and Mr. G. W. and Mrs. E. G. Peckham of Mil- 
waukee, Wis. M. Fabre has given us the results of his keen and 
careful observations in his interesting and delightful papers, “Souve- 
nirs Entomologiques.” The Peckhams published their equally in- 
teresting results with sound deductions on the instincts of animals 
in “Observations on the Instincts and Habits of Solitary Wasps”, 
Bulletin No. 2, Wisconsin Geological and Natural History Survey, 


| 
| 
| 


Some Solitary Wasps of Texas. 5 


1898. It was this work which first induced me to take up the 
study of solitary wasps as a summer’s recreative work and from 
which I have derived many helpful suggestions in my study. The 
remaining literature on the subject comprises short papers that 
record, for the most part, only individual observations. 

Most of the observations recorded in the present paper were made 
in July, August and September of 1903. The work was not done 
continuously during this time, but in periods of from three to four- 
teen days, because of frequent interruptions, chiefly on account of 
rains, which were very heavy and long continued, drowning out 
many wasp larvae. 

The scene of action of these exciting dramas of insect life was 
the sandy woods five miles southeast of Austin, on the high south 
bank of the Colorado River. The woods are a favorable place for 
studying solitary wasps, for they are numerous both in species and 
individuals and it is, moreover, easy to observe and to follow them 
because the sandy soil will support but a sparse vegetation, in which, 
in less favorable places, a wasp is often lost to view. In point of 
comfort to the observer, the woods offer a decided advantage, for, 
in the first place, he can often make use of the inviting shade of the 
spreading post-oak and hickory trees, though he often has to resort 
to his umbrella for protection against the burning rays of the sun. 
Wasps, it must be remembered, revel in hot, clear days and work 
best in the heat of noon-day when the mercury is flirting with the 
100 mark. Indeed, on dreary days most of the wasps will not 
work at all, but will fly listlessly about, sipping nectar from the 
flowers. The second point of comfort is derived from the absence 
of “red bugs” and ticks. These pestiferous creatures are found 
on vegetation and since almost the only herbs found in the woods 
are grass-burs and bull-nettles, which one assiduously avoids any- 
how, it follows that one collects few, if any, “red bugs” and ticks in 
the place in question. 

The observations are recorded below by species and theoretical 
considerations have been intercolated wherever it was deemed nec- 
essary or desirable. These latter have been summed up in the 
“Conclusions” at the end. 

I wish to take this opportunity of thanking Dr. S. Graenicher of 
Milwaukee and Dr. H. W. Ashmead of the Smithsonian for the 
identification of the Solitary and the Parasitic Wasps. 


I. TWO EUMENIDAE. 


(a) OpyNEeRUS DorsaLis, Fasre. 


On September 2d, just before noon, I was walking through a 
cornfield and chanced upon a wasp that had just dropped clumsily 
on the ground between the blades of a clump of grass. I had, 
several days before, seen another individual of the same species 
drop down in a similar place and caught her without searching the 
premises. ‘This time, however, having become more suspicious, I 
waited and watched. The wasp moved about slowly for a while, 
always looking at me with what seemed a stare, which was due to 
two yellow spots like eyes on the sides of her face. Gradually she 
walked further back; and as I stooped, I saw under the grass five 
neat mud cells. One of these was open and contained several small 
caterpillars (cotton-worms) already stored away. Soon the wasp 
flew away, presumably after more prey; I should have awaited her 
return and watched every step of the work of storing and building 
had not some digger wasps engaged my attention at the time. I 
therefore left the place before the wasp had returned. At 2:30 
I went back to ascertain Mme. O.’s progress and found that 
the open cell had been closed with an out-turned saucer-shaped mud 
lid and that another cell had been begun. By 6:30 in the evening 
this was finished though still open and was occupied not by cater- 
pillars, but by the wasp herself, which was lying inside and looking 
contentedly out. At 11:25 o’clock the next day the wasp must 
have been at work for several hours, for the cell had been nearly 
filled with caterpillars, which is the condition shown in Fig. 3. At 
11:52, she came back carrying another caterpillar in her mandibles. 
I had pulled away some of the grass-blades above the nest and 
had my camera set up to take the picture of the nest. But this dis- 
concerted her very little, and I was surprised at the ease with 
which she became accustomed to the change. After once flying 
away for a minute and circling about once or twice, she settled and 
placed the caterpillar in the nest. This was done in a peculiar 
manner. The wasp laid the caterpillar down at the opening of the 
cell and supported herself with her fore-feet on the edge. She then, 
with her mandibles, passed the caterpillar on as far as she could 


Some Solitary Wasps of Tezas. 7 


reach, took a second hold and pushed it on further, repeating the 
operation until the whole length of the caterpillar was inside. 
Then she crawled up and with her head stuffed all the caterpillars 
as far back into the chamber as possible. This done, she cleaned 
her antenne and flew away without seeming to take her bearings. 
She had evidently made so many trips to the spot that a study of 
the locality had become unnecessary. 

By 7 p. m. the cell had been closed and another built, which 
the wasp was occupying for the night. A day’s work with dorsalis 
evidently consisted of storing a cell, closing it, and building another 
to be used in the first instance as a lodging place for the night. 
Thus I found her still at home at 7:45 the next morning (Sep- 
tember 4th), as shown in Fig. 4. She was lying in the cell, which 
her body comfortably filled, and was amusing herself with picking 
up unwary ants that chanced to pass too close to her threshold 
and, like the Harpies of old, grinding them in her jaws. I allowed 
her to store this cell, as well as build another; then I caught her 
and carried the cells home. 

O. dorsalis. builds pretty mud-cells on the ground, choosing a 
place hidden from view by a clump of grass. The cells are broadly 
spindle-shaped, pointed at one end, which is left open until the 
cell is stored. The chambers do not touch each other for more 
of their length than is necessary for their mutual agglutination. 
This almost entire independence of the cells entails a considerable 
waste of building material as compared with the habit of Pelopaeus 
cementarius, which builds her cells side by side in rows 
and tiers of rows. It seems probable that the former method is 
the more primitive one, and that the latter has been superinduced 
by the mud-dauber’s habit of building on flat surfaces. It is to 
be noticed that the lumen of a mud-dauber’s cell still remains, in 
spite of the irregularity of the outer surface, cylindrical. The 
entire structure made by dorsalis is not only held together by the 
slight adhesion of the more or less fragile cells which compose it, 
but is also partially suspended by grass-roots imbedded in the 
plastered walls. The shape of this nest with the grass-roots at- 
tached can best be seen in the figures which are photographs taken 
at different stages in the construction. (Figs. 3, 4, 10, 11.) 

The first wasplet emerged on October 7th, the others on October 
8th, 9th, and 11th, respectively. One wasp failed to emerge and 
was probably from the fourth egg laid, and would normally have 
emerged on October 10th. If one cell was stored each day, the 


8 Some Solitary Wasps of Texas. 


first egg laid was on August 30, and the total period of develop- 
ment would be thirty-nine days. The wasps emerged (Fig. 11) by 
a small round opening gnawed in the cell wall. This hole was 
in three cases near the last sealed end, in one case at the opposite 
end. 

One cell, the last one stored, I broke open to examine the con- 
dition of the caterpillars. I was especially anxious to see this, 
as I had once observed a specimen hang from a twig by one of 
the hind legs and chew the head of a cotton-worm, holding the 
caterpillar with her front and middle legs. I had often seen 
Microbembex do this in exactly the same way, and as this species 
feeds her larva on any insect, dry or fresh, or on any part of an 
insect in almost any condition, I concluded that she sucks as much 
of the insects’ juices as she needs for her own sustenance and 
feeds the rest to the larva. Charles Janet has likewise observed 
this with Vespa crabro, where the workers, when the colony is 
threatened with over-population, kill some of the larve and pupe, 
suck their juices and feed the remainder, rolled up in balls, to 
the surviving larve. In the case of Odynerus, I am pretty certain 
that she takes a caterpillar occasionally for her own delectation. 
I could draw quite near to the chewing individual and could see 
every movement, even of the mandibles, during the process. The 
condition of the caterpillars in the cell I opened, moreover, pointed 
to the fact that in chewing the caterpillar she was not preparing 
it for her offspring, but was satisfying her own hunger. Of the 
seven caterpillars found in the one cell, all were in good condition, 
and four responded very perceptibly to stimulation, one of the 
latter moving spontaneously. All remained in practically the same 
condition until attacked by the growing larva. (Fig. 10.) 

I watched the growth of the larva until it was ready to spin 
its cocoon (September 26th). But as I had torn away a goodly 
part of the wall of the cell, it could not spin its cocoon all around 
and died. But the absence of the wall was not the chief cause of 
the pre-pupa’s death. When I returned to her on October 7th, 
I found the pupal skin completely covered with egg cases of a 
parasite. On close examination, these proved to contain myriads 
of mites in various stages of development. Such egg-cases I have 
often noticed on dead digger-wasp larvee, and they usually appear 
on the articulating membranes between the segments. 

From cell No. 4 the imago failed to emerge. In November, when 
I broke open the cell, I found the nearly mature wasplet dead. 


Some Solitary Wasps of Tezas. i] 


The cause of its death was easy to understand, as I found protruding 
from the sides of its abdomen a number of the egg-cases above 
mentioned. 

As regards the length of developmental periods, the above data 
only give the total length of development as thirty-nine days and 
that of the egg and larva together twenty days. 


(b) OpyNERUs ARVENSIS, SAUSS. 


This species of Odynerus does not posssess the architectaral skill 
of its cousin just described. Its home is not such an elaborate 
domicile, built, as it were, for show as well as for use, but consists 
of any convenient crevice in a wall or fence-post. — The nest is 
completed by closing the opening of the crevice with mud, much 
after the fashion of Tryporylon. I have made a few observations 
on two nests of this Odynerus; those on the conditions of the cater- 
pillars found in the nests are of particular interest. In general, 
the following facts do not justify Fabre’s conclusions which he 
based on the habits of O. rentformis. 

At noon, August 4th, a female arvensis was closing her nest 
in the niche of a brick wall. A few days before a Trypoxylon 
had emerged from the very niche now intended to be the cradle 
of another wasplet. I immediately opened the nest and drew out 
eight caterpillars, all of which were alive, six of them, in fact, so 
lively that they wriggled around in the small vial to which I had 
transferred them. I found no egg at first, but, looking carefully 
into the dark recess, I discovered the egg suspended from the 
ceiling of the little room. After breaking the suspensory thread 
with a knife and brushing the egg out, I placed it among the 
caterpillars in the bottom of the vial. Very few wasps’ eggs could 
stand the rough handling which this egg received. The explanation 
of its endurance lies in the toughness of its shell. The larva 
hatched in two and one-half days, having shed a tough, translucent 
shell which could safely be handled with a pair of forceps. After 
fifteen hours the larva had attached itself to a writhing caterpillar 
and had grown perceptibly. The remaining data are as follows: 

August 9. Five days after the nest was closed, two caterpillars. 
have been devoured and the remaining six are still alive, of which 
four move spontaneously. The wasp larva is as large as one of 
the caterpillars. The larva takes a long rest this morning. 

August 10, 6 p. m. All parts of all the caterpillars have been 
devoured, 


10 Some Solitary Wasps of Tezas. 


August 11, 6 p.m. Larva nearly finished spinning cocoon. 

August 29. Adult emerges. 

Thus the length of the egg stage of O. arvensis is about two and 
a half days; of the larval stage, four and a half days; of the pupal 
stage, eighteen days. 

Another nest which I observed an arvensis store and close on 
August 14th I opened nearly a month later (September 9th). I 
was expecting to see a wasp emerge by this time, and had placed 
a bottle over the entrance to receive it. I found in the nest no 
offspring of the wasp, but the red pupa of a fly and fourteen cater- 
pillars, of which four had dried up, three were dead though in 
good condition and seven actually alive. The caterpillars’ length 
of life is so striking that I deem it desirable to add the following 
table: 


CONDITION OF CATERPILLARS. 


Date Begun to shrink.|/Dead but plump. Alive 
September 9.........0....... 4 3 7 
Re piemiper «1. a eee 5 5 
September 19.0000... 5 1 4 
Sephem ber (26 i he eos 2 3 
September 29................ 3 1 1 
October 11 1 


Thus three caterpillars lived 43 days, one 46 days and one re- 
mained, for 58 days, in a condition good enough to be added to any 
waspling’s bill of fare. 

A survey of these few facts would seem to indicate that, while 
the suspension of the egg and the young larva is a desirable con- 
dition and increases their chances of successful development, yet 
it is not an essential condition, as Fabre has contended. Nor is 
it essential, in consideration of the longevity of the paralyzed prey, 
that the caterpillars be devoured in the order in which they were 
stored. 


II. AMMOPHILA PROCERA, DAHLB. 


Ammophila is perhaps the most famous of all the digger wasps. 
Her homing faculty is most wonderful and is perhaps mainly re- 
sponsible for the assumption of the sixth sense in insects, the sense 
of direction ; the accuracy of her stinging instinct was long regarded 
as perfect. She has been several times observed to use a pebble 
as a tool with which to tamp the ground, so that a claim for 
her superior intelligence will not easily be contradicted. She is, 
moreover, a delightful subject for observation because of her tol- 
erance of human company as well as her easy grace and her calm 
and dignified, though business-like ways. 

In the course of the summer I was fortunate enough to observe 
six different individuals of Am. at work, four of which allowed 
me to witness the carrying home and storing of the caterpillars, 
while two individuals performed for me the whole process of dig- 
ging, storing and closing up the nest, leaving me in the dark on 
only one step of the process, namely, the capture of the prey. All 
the individuals observed belonged to the species procera. It in- 
cludes the most formidable members of the genus in America. The 
species is very variable in size. Five of the specimens whose ac- 
quaintance was made were among the largest; the sixth was much 
smaller and differed from the others in the number of caterpillars 
captured, as will be seen below. In the present description of 
Ammophila’s habits, I shall follow the whole history of a nest 
from the beginning. 

When Ammophila feels the necessity for doing so, she flies around 
in search of a suitable place to dig her nest. She is hard to satisfy 
in this respect, for I have seen her alight at a dozen different places 
and begin to dig before she finally decided on a place as good 
enough. ‘To test the ground she does not waste time by digigng 
long at any one place, as does Pompilus, which often abandons six to 
eight half-finished nests before deciding on one to suit her; but 
Ammophila merely scratches the surface a little and, if dissatisfied, 
flies or runs off to another place. Some over-fastidious indi- 
viduals have been known, however, to abandon the old nest and dig 
a new one near by after the former or even the ground around it 
had been slightly disturbed. 


12 Some Solitary Wasps of Texas. 


After the location has been chosen, Ammophila does not waste 
any more time deciding what to do next, but sets to work digging 
her nest, the tomb of her victim and the birthplace of her offspring. 
If the surface of the ground is dry and sandy, the hole is started 
' by scratching out the sand with the front legs as is usual with most 
digger wasps. These use their front feet during the whole digging 
process, employing their mandibles only to bite loose the more solid 
earth or to break up the larger lumps. If the ground is hard at 
the surface, Ammophila begins by biting off pieces of earth and 
carrying them to one side, continuing this method until the nest is 
finished. The need of this mode of excavation as compared with 
the scratching method employed by most digger wasps becomes ap- 
parent when the shape of the nests are taken into consideration. 
The tunnel leading to the pocket of Ammophila’s nest is nearly ver- 
tical (Figs. 22 and 18), while the nest of other digger wasps is a 
nearly horizontal tube with a slight dilation at the end (Figs. 19 
and 21. Fig. 6 represents Ammophila beginning her nest by bit- 
ing the ground loose with her mandibles. Fig. 13 shows the nest 
farther advanced with the wasp already reaching down to bite off a 
“mouthful” of dirt. The work progresses rapidly, for Ammophila 
is a zealous and steady worker. Only now and then does she fly up 
and circle about a little to fix the locality of the nest in her mind. 
At first sixteen to eighteen loads of earth are carried out a minute, 
and as the nest deepens the time required for going in and out in- 
creases, so that as the nest nears completion, only eight to ten trips 
are made to the surface per minute. The wasp goes down the hole 
head first and backs out, turning around at the surface and run- 
ning over to the dumping ground a few inches away. Here 
the load is flung down with a flirt accompanied by a joyful, enthusi- 
astic buzz. After thus hurling away the lump of earth Ammophila 
gives a jump, turning suddenly face about, and goes back, half run- 
ning, half flying, after another load. Fig. 22 shows the pile of sand 
carried out by the wasp on the left of the picture, i. e., on the side 
of the nest opposite the pocket towards which the entrance gallery 
slopes (at x). 

The work of excavation occupies about thirty-five minutes in the 
loose soil of the woods where the observations were made. The com- 
pleted nest, in general always characteristic of the species, varies 
somewhat with the individual and the condition of the soil in which 
it is dug. From above (Fig. 8) the nest appears as a perfectly 
round hole about half an inch in diameter leading nearly straight 


‘ 


~~ 


Some Solitary Wasps of Texas. 13 


down as far as one can see. Where the surface of the ground is 
soft and dry, the hole will be wide-mouthed like a funnel, due to 
the caving in of the sides. 

On cross-sectioning the nest its true shape is revealed. The gal- 
lery, nearly vertical near the top, runs down in a gentle curve till it 
becomes nearly horizontal, where it widens out into a spacious 
pocket which received the caterpillar. Fig. 22 represents a nest of 
average size and typical shape. ‘The distance from the mouth to 
the farthest end of the pocket is three inches; this is 34 inch high 
and 11% inches from the surface of the ground and the tunnel is 3 
inch in diameter. The pile of excavated sand at the left is 3 inches 
from the entrance. Fig. 17 represents two smaller nests also dug 
by large individuals. The nests are of a different shape from the 
typical. Both have short tunnels; the pockets, one inch below the 
surface of the ground, have their long axes at right angles to the 
tunnels, 

After the completion of the nest, the next problem confronting 
Mme. Ammophila is the procuring of a supply of food for her 
future offspring. Caterpillars always constitute the victim of the 
Ammophile, and the number varies with the species of the wasp 
and the size of the caterpillars. The large individuals of procera 
capture and store but one immense green “tomato” caterpillar, 
the subject of the photographs. The smaller store several small 
caterpillars of about the same length of their own body. 

Before setting out on the chase, some species of Ammophila take 
the precaution of making a temporary closure of the nest, particu- 
larly if the provisioning is to be postponed to the next day, and 
the degree of care with which the closure is effected varies with 
the species and with the individual. A lump of earth may be 
laid over the entrance and this covered with a number of pellets 
so as to make the location indistinguishable. Another individual 
of Ammophila urnaria has been observed by the Peckhams to wedge 
a good sized stone deep into the neck of the burrow and then fill 
the space above, solidly, with smaller stones and earth. A 
third individual of the same specie neglected to close the nest 
at all. Fabre describes Ammophila argentata and Ammophila 
sabulosa as closing the nest immediately after it has been made, 
but Ammophila holosericea as leaving it open until it is com- 
pletely stored. The last mentioned species stores five to six cater- 
pillars, and Fabre thinks she leaves the nest open on account of 
the inconvenience of closing it so often. Dr. Williston, however, 


14 Some Solitary Wasps of Tezas. 


has observed Ammophila varrowi take the greatest pains to close 
and conceal the entrance each time a caterpillar is brought in 
though she stores four to five of these. This is also the case with 
the smaller procera observed by me, for when she brought in the 
third caterpillar she scratched out much sand, bits of wood, etc., 
which she threw away. Finally she pulled out the plug at the bot- 
tom which she laid down close by for use at the final closure. The 
five larger specimens of A. procera observed by me agreed with the 
French hirsuta of Fabre, in that each stored but one large caterpillar 


and was thus relieved of the necessity of closing the nest. Procera _ 


differs from her French cousin in that she digs her nest before catch- 
ing her prey as two to six hours elapse between the digging of the 
nest and the bringing home of the prey. It is thus seen that the 
habit of closing the nest while the wasp is off searching for her 
prey does not depend on the number or size of the caterpillars but 
seems to have developed independently and to different degrees in 
the different species and is by no means constant for any given 
species. 

At 9:40 a. m. on July 22d, while busy observing the doings of 
Monedula carolina I saw a small Ammophila running over the sand 
carrying a good sized caterpillar in her mandibles. She soon 
dropped her victim and flew away, preumably to visit the nest and 
make sure of the road. In a few moments the wasp came back and 
searched right and left for the caterpillar. Twice she passed within 
two inches of it without noticing it, which would seem to indicate 
a rather weak sense of smell. 

Again the caterpillar was picked up and carried off at the rate 
of five feet a minute over obstructions in the way, to her nest located 
in the shade of a clump of saplings. Here the caterpillar was laid 


down on a smooth surface several inches in diameter where the wasp > 


began to open up its nest. Sand and dry twigs and leaves were 
pulled out and cast away promiscuously. The last piece of wood 
brought up was the largest and most compact and was not cast 
away like the others but was carefully laid down near the entrance. 
Ammophila did not forget the caterpillar during these few minutes 
but frequently approached and touched it with her antennae. When 
all was ready the wasp backed into the tunnel, got hold of the 
caterpillar and pulled it down. The caterpillar was sufficiently 
alive to grasp a blade of grass and hold on, but the wasp tugged 
till it had dragged the caterpillar into its grave. 

After remaining inside three minutes, the wasp came out, walked 


a 


Some Solitary Wasps of Texas. 15 


around a while and finally picked up the chip which it had taken 
out last and replaced it in the tunnel, reaching down as far as 
possible to press it in. This plug of wood probably served as a 
shelf to receive the bits of rubbish and the sand with which the 
tunnel was now being filled. Dry leaves and twigs were dropped 
into the hole and sand scratched in on top of these while all was 
stuffed down with the head. In eleven minutes the nest was filled 
and smoothed over. Ammophila then flew away and returned three 
times, remaining away eight minutes at a time. The nest which 
the mother wasp was soon to leave forever, seemed to have had a 
strange attraction for her. The last time she returned (at 10:27) 
she carried pieces of leaves and earth over the nest as if she wished 
to obliterate every trace of the work. 

This small Ammophila, having to bring in three caterpillars, 
which necessitates making three hunting trips to store the nest, is, 
of course, benefited by closing up the nest each time before de- 
parting to keep out the flies and Mutillids bent on mischief. Her 
larger sisters are powerful enough to carry off the largest cater- 
pillars ; they therefore capture a single victim large enough to sup- 
ply the larva and so have no need to close the nest while on ‘the 
hunt, which may occupy from two to five hours. 

It is a strange sight to see a large Ammophila carry her heavy 
burden home to the nest. The grass green caterpillar and the 
slender black wasp with her red metallic wings and abdomen girdled 
with bright red form a marked contrast to the grey sand over 
which they glide. It is a sight that never fails to excite one’s in- 
terest to the utmost. One can not but admire the wasp for her 
immense strength and wonder that so small a creature can carry 
such a load. In spite of the disproportion between the wasp and 
the boat shaped burden, her rate of progress is rapid enough for she 
travels along at the rate of ten feet a minute over sticks, clumps of 
grass and inequalities of the surface. (Fig. 16.) 

The most wonderful thing about Ammophila, however, is the 
almost unerring manner with which she finds her way back to the 
nest. Sometimes, it is true, she will drop her burden temporarily 
to fly away and assure herself that she is on the right road. But 
usually she will march on uninterruptedly in one general direction 
and come exactly to her nest in spite of the hundreds of crooks and 
turns around the various obstructions in her path. 

Having arrived at the nest the caterpillar is laid down and the 
wasp goes inside to see that the way is clear and to determine 


16 Some Solitary Wasps of Texas. 


whether the tunnel is large enough to admit the caterpillar, for the 
wasp always, before pulling the caterpillar in, brings out a number 
of mouthfuls of earth and on each trip approaches the caterpillar 
as if to measure its thickness. Sometimes only a few, and some- 
times many trips are made before the caterpillar is taken inside and 
it is usually a tight fit and requires considerable tugging on the 
part of the wasp. 

Before the caterpillar is pulled in it is dragged over to the nest 
and laid down with its head nearest the entrance. Then the wasp 
backs down, grasps her prey with her mandibles and pulls it in. 
Ammophila usually remains inside five to six minutes to arrange 
the caterpillar and to lay the egg. Figs. 18 and 22 show the posi- 
tion of the egg (4 mm. in length) of one wasp which fixed it on the 
10th segment from the head. The position varies anywhere from 
the 6th to 10th segment. The egg is always securely attached by 
one end (the head end of the embryo) to the side of the cater- 
pillar and points with its free end towards the caterpillar’s venter. 
When the larva hatches it occupies the same position that the egg 
did. It merely pierces the skin at the old point of attachment to 
suck the caterpillar’s juices. 

Ammophila now proceeds to close up the tunnel and leave her 
offspring to its fate. The tunnel is usually closed very carefully ; 
some individuals are more or less careless, however, as were Nos. 
72 and 73 whose nests are represented in Fig. 17. One nest was 
left open, the other was closed in a very perfunctory manner. 

Ammophila searches in a radius of a yard and picks up large and 
small pieces and carries them to the nest (Fig. 8). If the piece is 
too large the wasp may carry it to the nest and try to fit it in or 
may discard it before she gets to the nest. She seems to have the 
power of judgment to a certain degree, for she evidently is able 
to determine whether a thing is too large to suit her use or not. 
Not only is debris thrown into the nest but the wasp alternates by 
scratching in the loose sand at the surface and tamping it down 
with her head. When the nest is full enough for the wasp to reach 
down comfortably she presses the separate pieces firmly down before 
she lets go and accompanies the strenuous operation with a cheer- 
ful buzz. Now it sometimes happens, especially towards the end of 
the operation, that a piece of wood is pressed down tightly, then 
pulled out and pressed down again and this repeated several times, 
so that one might suspect that the wasp were here improvising a 
tool with which to tamp down the sand. Indeed this very act was 


—_— 


—- » 


Some Solitary Wasps of Tezas. 17 


observed by the Peckhams and Dr. Williston on Ammophila urraria 
and Ammophila Yarrowt. In each of these two cases the wasp 
used a pebble to tamp down and smoothe over the ground, not once 
merely, but several times, laying the pebble aside each time while 
she brushed on more sand. The use of the piece of wood by Ammo- 
phila procera in a similar manner is not so decisive since she presses 
a number of articles into the nearly closed entrance before she uses 
the last piece in any way approaching its use as a tool. Perhaps the 
use of the pebble by A. Yarrowt, the prairie species, is an extension 
of the more generalized habit of procera which lives in the woods 
where rubbish of all kinds is easily accessible and the whole tunnel 
is filled with it as shown in Fig. 18. 

After the nest has been closed and the tunnel filled flush with 
the surface, sticks, whole leaves or blades of grass, ete. (things 
are not too large now), are carried over the nest to obliterate all 
traces of the wasp’s work. In fact this is sometimes so skillfully 
done that unless one makes a mark he fails to find the nest again 
except by cutting vertical sections in the direction of the nest until 
this is opened. 

The process of thus concealing the nest is, or course, highly pro- 
tective to the human eye, though it can hardly be its real purpose 
to delude man or to entertain an admiring observer. The habit 
is probably a mere extension of the one which impels the wasp to 
carry debris into the tunnel to hold the sand which helps close the 
entrance. 

The finishing touches having been applied, Ammophila is usually 
off and away immediately, though sometimes the fond mother seems 
unable to sever her connection with the nest so recently made and 
remains in the neighborhood visiting the nest occasionally to make 
a few changes. Once J caught a wasp in a neighboring tree after 
she had apparently finished her work; but she escaped through a 
hole in the net. For the next hour she continued to come near 
the nest again and again though she assiduously avoided me and 
my net. Gradually, however, she seemed to forget her experience 
and became so bold that I could approach close to her and easily 
captured this artist of her race. 

Fig. 17 represents a section of the nests of wasps Nos. 72 and 
73. It is a rare thing to observe two Ammophilae digging their 
nests so close together at the same time. Their behavior under 
these conditions seems to me to justify a special description of them 
here, 


18 Some Solitary Wasps of Tezas. 


When on September 18th an Ammophila flew up in front of me, 
I knew from her actions’ that she had business interests in the 
neighborhood and so. repaired to the inviting shade of a hickory 
‘tree to observe her. She settled and began to dig near an open 
-Ammophila nest and I supposed that it belonged to her and that 
she was just closing it up. But she continued to dig another nest 
close by. Her work was not destined to go on smoothly, however, 
for hardly had five minutes passed, when a second individual (No. 
‘73) came strutting along bearing a large green caterpillar. Wasp 
No. 72 remained ignorant of the approach of her sister until the 
‘latter came somersaulting over a stick at which the former was 
working. A fight ensued, the two clinching several times and even 
drawing their deadly weapons. They then flew away and No. 73 
was the first to return. She took up her caterpillar, carried it to 
her nest, but returned to it, laid the caterpillar down, and pro- 
ceeded to carry out sand as usual. At 2:02 No. 72 came back, 
-while No. 73 was within her nest hidden from view, and was about 
to make off with the caterpillar which she found so handy. The 
rightful owner intercepted the thief, however, and in another duel, 
succeeded in recovering the purloined property. She then took the 
caterpillar up and carried it off for a distance of two feet, where she 
stopped to reconsider. It seems that the struggle for the recovery 
of the caterpillar must have reminded the wasp of the struggle 
to capture it, and that her next idea was to carry the caterpillar 
home, but she discovered her mistake in a moment. It certainly 
looked as though some such reflections were going on in the mind 
of the wasp. After hesitating a moment she turned around, carried 
_ the caterpillar back, laid it down at the entrance and hurriedly car- 
ried out only one mouthful of sand before dragging the caterpillar 
within. She then closed the nest in a slipshod manner and flew 
away at 2:23. 

No. 72 returned and finished her nest without interruption where 
she had begun. By 6:45 she had not yet returned with her prey 
and I feared that she would not, since it was already very cool and 
since there were chances of her having been hurt in the struggle. 
She brought home a caterpillar, however, as I found one in the nest 
several days later, though she did neglect to close the nest. I found 
~ both caterpillars in good condition (Fig. 17) but without an egg. 
It is possible that in the duel the mature eggs, ready to be laid, 
- were lost. Thus affairs sometimes go wrong even with the brilliant 
Ammophilae. 


Some Solitary Wasps of Texas. (19 


It is a significant fact Ammophila No. %2 picked up the 
stranger’s caterpillar and walked away with it when she did. She 
had not yet dug the nest and therefore, according to Fabre, the 
instinct to procure her prey should not have yet manifested itself. 
This author experimented on Sphex ichneumonea which places her 
grasshopper at the entrance to her nest and then runs in and out 
again before dragging it down. He took advantage of a moment 
when the wasp was out of sight below to move the prey to a little 
distance, with the result that when the wasp came up, she brought 
her cricket to the same spot and left it as before, while she visited 
the interior of the nest. Since he repeated this experiment about 
forty times, and always with the same result, he concluded that 
nothing less than the performance of a certain series of acts in a 
certain order would satisfy her impulse. The Peckhams tried the 
same experiments and found the American S. ichnewmonae would, 
after being fooled five or six times, carry the grasshopper inside in 
various ways but without first running down. It is thus apparent 
that wasps may perform certain instinctive acts though they be out 
of the usual routine, as was the case with my Ammophila which 
was about to procure the caterpillar before she had dug her nest. 

The stinging habit of Ammophila and the resultant condition 
of the caterpillars have long been subjects of both the reason and 
the imagination among naturalists. J here append my own ob- 
- servations on the condition of the caterpillars. A discussion of the 
subject follows in the concluding chapter of this paper. 

Notes on the condition of Ammophila’s caterpillars. 

I. No. 16. July 22d, 9 a. m., three small caterpillars, all re- 
spond to stimulation. 

July 23d, 6 p. m., caterpillar containing ege dead, others still 
alive. 

II. No. 28. August 17th, caterpillar responds to stimulation 
at both ends of body. 

August 20th, more lively than on August 17th. 

August 23d, it is nearly dead. 

Ill. No. 55. Egg laid 4:50 p. m., September 1st. Caterpillars 
move both ends of body spontaneously. 

September 3d, caterpillar passed foeces twice and is more lively 
than the day before, moving front legs and posterior end of body 
spontaneously. 

September 4th, 7 a. m., egg apparently hatched, larva occupying 


20 Some Solitary Wasps of Texas. 


same position as egg. 4 p. m., caterpillar has passed fceces again ; 
will move only on stipulation; larva growing. 

September 5th, 9:30, larva 6 mm. long, still occupying same po- 
sition ; caterpillar shrunken and nearly dead; can move head end 
on stimulation. 

September 6th, a. m., larva nearly as long as caterpillar is wide. 
Sucking movements visible in larva. 

September 8th, larva has sucked the skin of caterpillar dry and 
is devouring parts of this. 

September 9th, caterpillar all eaten up except head and tail. 
Fig. 9 shows full grown wasp larva with a remnants of a devoured 
caterpillar together with a fresh eaterpillar for comparison. 

IV. No. 61, September 5th, caterpillar moves both ends slightly. 

September 8th, egg dead. Caterpillar nearly dead; only extreme 
ends capable of slight movements on irritation. 

V. No. 72. September 18th, first four and last three segments 
movable; has turned pink. 

September 22d, head end responds to stimulation. 

September 26th, posterior end jerks when pinched. Anterior end 
is shrinking. 

September 27th, posterior end still alive, anterior end stiff. 

VI. No. 73, September 18th. Head and last two segments move 
a little on stimulation. 

September 22d. Several anterior segments respond to stimula- 
tion. 

September 25th. Dead. 


III. BEMBEX TEXANUS CR. AND MICROBEMBEX MONO- 
DONTA, SAY. 


Microbembex and Bembex (Fig. 2) are both common in the 
sandy woods, where they often form large mixed colonies, build- 
ing their nests side by side in great numbers. When a novice first 
comes upon one of these populous colonies on mid-day, when busi- 
ness is at its height, he is bewildered by the great number of wasps 
engaged in the general hubbub around the many holes that riddle 
the ground (Fig. 24). What confuses him more than anything 
else is the presence of the two kinds of wasps that look and act so 
much alike. Gradually, however, he becomes accustomed to the 
sight and soon begins to be able to distinguish easily the two species 
as they rest on the ground, 

Microbembex monodonta is somewhat smaller and more slender 
than Bembea Tex. and the stripes across her abdomen are greenish 
yellow, while those of Bembex are yellowish blue. With practice 
one soon learns to distinguish the two species at a glance, by their 
actions as well as appearance. The manner of flight is character- 
istive in each case. Bembex, as she flies around, is always in a 
hurry, flying in a zigzag course and giving a buzz at each sudden 
turn like a blue-bottle fly. Microbembex is calmer in her move- 
ments, she never seems in a hurry but flies gracefully about like a 
bird skimming the water. Particularly on the hunt, as will be 
pointed out below, is the diffeffrence very marked. Often while 
digging in front of the nest the wasps will rise and leave their work 
for a moment, especially if disturbed by idlers flitting leisurely 
about. Bembex Tex. usually settles immediately to resume work, 
but Microbembex considers the interruption an opportunity to take 
a few moments of well-earned rest and bask a while in the sun- 
light. 

Both of the species under consideration go through about the 
same actions in digging at their nests, the only difference being 
the quicker and more nervous ways of the smaller species. Here 
we notice the manner of digging in general characteristic of all 
the Bembecids. The body of the wasp, balanced, as it were, on 
the middle pair of legs, represents a teeter-totter in miniature. 
Each time the head goes down, the tail bobs up and a stream of 


22 Some Solitary Wasps of Texas. 


sand pours out from under the wasp, propelled by several smart 
strokes of the front legs in quick succession. Then there will fol- 
low.a brief pause while the wasp rests with head in air as if look- 
ing around an instant to survey the landscape. 

Activities in one of these Bembecid colonies does not begin until 
the rays of the sum have warmed the ground; and when the rays 
beat down from above, business is at its height and a gentle hum 
betokens the hustle and bustle of the inhabitants. When one visits 
the colony early in the forenoon, when scarcely a wasp is about, com- 
paratively few of the nests are visible, since'Microbembezx closes up 
her nest from the outside and sleeps elsewhere, while occasionally a 
Bembex Tex. will have her nest closed from the inside. Towards 
ten o’clock, however, the doors are thrown open, one by one, and 
soon the actual population of the colony is manifested. On cloudy 
days, the wasps are not as busy, but lounge about, often resting for 
hours at the entrance and looking out upon the world. 

Having thus located ourselves in the midst of this mixed colony, ~ 
I shall follow Microbembex more closely and leave a detailed de- 
scription of Bembex texanus for a time, when I shall have collected 
more data on this interesting wasp. . 

Microbembex is unique among the solitary wasps in the variety 
of the insects with which it feeds its larval offspring. Bembex takes 
several species of flies, but never anything but flies; similarly, a 
bug-catcher takes only bugs and a spider-ravisher only spiders. The 
greatest variety of the prey of the solitary wasps of which I can 
find any record is Monedula punctata described by Bates, who says 
that this species catches fire-beetles as well as flies. Our Micro- 
bembex will take home for provisioning its nest and insects that it 
finds already dead, or it will capture the living prey. On account 
of this great variety of food, I shall give a detailed list of the ar- 
ticles of food together with notes on the behavior of the wasps in 
capturing or in carrying home the prey. ae 
~-(1) Slender red caterpillars, 114 inches long. I saw five of 
these carried home by different individuals. The caterpillar is 
carried home on the wing, though not directly, because of the weight 
of the burden, but in spurts. The wasp grasps her prey by its. 
head with her mandibles and flies suddenly in a kind of jump to 
another point, one to three feet away, where she lays the cater- 
pillar down and rests. Sometimes the wasp will fly off for a 
_moment , leaving the caterpillar lying in the sand. When she re- 


Some Solitary Wasps of Texas. 23° 


turns, to search for her prey, she does so by flying slowly round and 
round in the vicinity of the caterpillar. 

' These tactics expose the prey to considerable danger ae para- 
sitic flies. Indeed, I once noticed two grey Muscids with reddish 
abdomens follow a wasp with her caterpillar for a great distance. 
Their persistence greatly agitated Microbembex, and she several 
times left the caterpillar and pounced upon one or the other fly 
and threw it to the ground. The blow was, however, not serious, 
for the fly continued without fear as before. Why the wasp did 
not kill the interlopers on the spot, I can not understand. Fabre, as 
well as the Peckhams, wonder at the laxness of Bembex in her treat- 
ment of parasitic flies which she keeps driving away instead of 
killing them once for all. This would be easy for her to do, if she 
were so inclined; a single sting, applied as it is to another fly that 
is to serve as food, would forever rid her of one of these trouble- 
some intruders. Both the French and the American observers fail 
to offer an explanation for the phenomenon. It may be that the 
sting is not used on other occasions than the capture of prey, just 
as is the case of the queen domestic bee the sting is never drawn 
except in mortal combat with a rival queen. Since it is always 
certain species of parasitic flies that are in attendance upon the 
wasps, it may be through mere familiarity with the flies, and the 
presence of those so near to the nest, that they are so much tolerated. 
For the flies are in every way treated like other wasps of the same 
species. I have seen a Bembex knock down another Bembex or a 
Microbembex and have even seen them clinch as if earnestly en- 
gaged in fighting, but they never drew their stings. 

Notwithstanding the half hearted efforts of Microbembezx to rid 
herself of her enemies, these follow her to her nest. Having ar- 
rived at the nest the wasp opens it, grasps the caterpillar with her 
hind legs and drags it inside, walking in head foremost. Ammo- 
phila, it will be remembered, backs into the nest and pulls her cater- 
pillar in backwards. 

- (2) Another common object brought in by Microbembex, was 
the leg of a grasshopper. On several occasions I saw this carried. 
along in the same way that the caterpillar was carried. Once an 
ant was making away with the leg of a grasshopper which it had. 
probably purloined from the Microbembez herself. The wasp many 
times picked up the leg but the ant would not let go, but forced 
the wasp to drop it, until the latter gave up the fight. 


24 Some Solitary Wasps of Texas. 


(3) Twelve small queens of ants. These had been dead for 
some time. They all probably came from the same spot, as they 
were brought home in quick succession. The nest was left open 
while the queens were brought in, which is an exceptional thing for 
Microbember to do. 

(4) Large red ant. (Pogonomyrmex Apache.) I once saw @ 
Microbembex pick up one of these fierce species and fly with it to a 
mesquit bush. There she hung from a twig by her front legs and 
held the ant with her other legs, while she bent her abdomen under 
her in her attempt to apply her long protruding sting. The ant 
seemed dead when I first saw the wasp pick.it up and had probably 
been stung before; or the wasp may just have found the ant dead. 
That Microbembex does attack the living ants seems probable from a 
struggle I once saw between a wasp and two red ants, one of which 
had probably fastened its hold upon the wasp at the start until 
joined by the companion. The wasp was evidently dead when I took 
the two into a bottle with some sand. As I turned the bottle and 
so covered the insects with sand, the ants crawled to the surface and 
immediately began to dig down again to pull forth their dying ad- 
versary. 

(5) Flies of various kinds, particularly Syrphids. On one occa- 
sion I noticed a wasp fly to a weed and hang there by one of her 
hind feet while with the remaining five she held an apparently dead 
Syrphid. I could approach very close to her and could see how she 
held the fly and alternately apply her mandibles and proboscis to the 
fly’s thorax. It is probable that Microbember was this time enjoying 
a little fly-juice for herself. Her action reminded me of Odynerus 
dorsalis which hung from a bush in the same manner and chewed a 
caterpillar, which she never does when this is intended for her 
larvae. Most solitary wasps suck the nectar of flowers for their sus- 
tenance. 


While Microbembex was working on the fly, she several times. 


dropped it and found it again without any trouble, knowing evident- 
ly that the fly was to be found on a plumb-line from where it was 
dropped. Once when the wind blew the fly out of the plumb-line, 


the wasp had some difficulty in finding it, as she persistently search= 


ed where the fly should have been. Thus spider-catchers have 
learned to find their spiders if these fall straight down from the 
place where they have been lodged. 

(6) Bugs belonging to five or six different species and varying 


Some Solitary Wasps of Texas. 25 


from two to twelve mm. in length. Some of the bugs were per- 
fectly dry, others were fresh when brought into the nest. 

(7) Small tree-hoppers, Tettigonia bifida, Say, the species 
which form the sole prey of Allyson melleus and of Rhopalum ab- 
dominale. 

(8) Polistes rubiginosus, so dry that it broke apart while Micro- 
bembex was carrying it. 

(9) Fresh grass-hopper, which I killed and threw on the nest- 
ing-ground, was picked up by a Microbembez, as was also a dry 
Syrphid. . 

(10) Dry yellow Mutillid. 

(11) Old Orthopterous pupa-case with dry dead pupa inside. 
Of all the things which Microbembex feeds to her larvae, these last 
two things are the toughest. The Mutillid must have been a most 
indigestible morsel, for the skeleton is so tough that in the fresh 
state it is very hard to drive a strong pin through it. The Mutillid 
was broken in two and the halves were carried off separately. 

The above account gives one a very fair idea of the diet of larval 
Microbembex. It thus seems probable that the larval food consists 
mainly of insects, which the mother finds already dead and often 
dry. This is, moreover, borne out by the manner of the wasp’s hunt- 
ing, in which she differs decidedly from the solitary wasps and re- 
sembles markedly Polistes and Vespa. Bembewx hunts her flies in 
a stormy fashion, flying around louder and faster than the prey 
she captures. Microbembex can be seen calmly flying through the 
woods much like a dragon fly, steadily maintaining a level of a foot 
from the ground. That she also attacks live insects is shown in 
that she attacks ants and in that her caterpillars are always limp 
and fresh. A fresh juicy caterpillar sandwiched in between a lot of 
old dry insects must indeed be a very welcome morsel for the grow- 
ing larva. 

It would thus seem that Microbember, contenting herself with any 
insect she finds, has an advantage over Bembez, her nearest relative, 
and Monedula, both of which feed their larvae from day to day. But 
quantity alone does not bring the advantage. No doubt Bembez, 
knowing the habits of her prey, and having developed a skill in its 
capture (being a specialist in the art of fly-catching), can collect as 
much real nutritive substance as Microbembex. Though more gen- 
eralized in the manner of procuring food, Microbembex has devel- 
oped an improvement in her condition over Bembex tex. in that she 


“se 


96 Some Solitary Wasps of Texas, 


closes her nest before leaving it, often smoothing it over with consid- 


erable care. In this way she is spared the inroads that commensal- 
istic laryae make into Bembez’s store of food. 

‘In their semi-social habit Bembex (and this would apply to Mi- 
crobembex) has been regarded as transitional between the truly soli- 
tary and the social wasps. Both genera are more solitary than social 
for their only social trait consists in a tolerance of each other’s pres- 
ence in the immediate neighborhood. Beyond an occasional quarrel 
or the stealing of éach other’s flies the wasps preserve the peace of 
the colonies. This recalls by way of contrast the fierce combat of 
two Ammophilae which happened to dig their nests near each other. 
Bember is furthermore said to show a social trait in the co-operation 


of the individuals in driving away parasitic flies. This is, however, 


more imaginary than real, for the fly is not killed nor is it driven 
away from the colony but merely from one individual’s nest to an- 
other’s. 

. Both Bembex and Microbembex are common species throughout 
the sandy woods. Every path or road or other area devoid of vege- 
tation is occupied by individuals of these flourishing species. If an 
open spot is a favorable nesting place, wasps may congregate there 
in numbers sufficient to riddle the surface with holes, thus forming 
an extensive colony. Now, since such spots are not common, the 
thought suggested itself that the very numbers of the wasps forced 
them to occupy the same patch of ground, to dig their nests side by 
side, and thus by virtue of their familiarity with one another to 
live together in comparative peace. The tolerance of one another’s 
presence would then be the first trace of the social instinct. The 
fact that the two different genera live together as peacefully as does 
Bembex with Microbembex seems to point to the same conclusion. 
Moreover, neither genus seems to show a marked predilection for 
living in the colony, for isolated individuals of both will be found 
throughout the woods, evidently as happy as when joining in the 
busy hum of a colony in the noon-day sun. 

. May it not even be that in this way numbers was the first stimulus 
toward social life as shown by a trace of it in Bembex and Microbem- 
bea? 


IV. SOME FLY-CATCHERS. 


. (A.) Monepuna Caroiina, Drury, THE Bie Fry Catcuer: 

~ Monedula carolina is our largest digger-wasp with the exception: 
of Ammophila procera. But the caterpillar-wasp looks comparatively 
weak, being slender, while the big fly-catcher has a most formidable 
appearance on account of her bulk and the warning yellow stripes 
ef her abdomen. In the hot months of the year the wasp is often 
met with in search of prey or digging her nest in the sand, where she 
cuts a conspicuous figure. You cannot proceed far through the 
woods before one of the big fellows will come flying toward you 
with the loud threatening buzz of a bumble-bee. The wasp will fly 
around you to examine you on all sides, keeping her face turned to- 
ward you and as you advance, she will advance with you flying back- 
ward before you. This backward flight of Monedula, almost unique 
among insects, recalls the habit of the South African wasp, cited 
by the Peckhams, which is said to fly backward before a moving 
horse and catch the flies hovering over it. On the authority of a 
friend of mine, I can say the same for Monedula, which often fol- 
lowed his ox-team, picked off the flies and “buried” them in the 
ground. I have myself seen as many as three carolinas around a 
horse or cow at the same time and there can be no doubt that they 
do not hover around for curiosity’s sake merely. 

- M. carolina spends three or four days digging her nest. The first 
two days she applies herself assiduously for hours at a time and will: 
scrape out an astonishing pile of sand. Her working hours are, 
however, extremely irregular, especially on the third and fourth 
days. She may return to her nest at any time of the day, taking 
an hour or two for recreation in the midst of her work. I have seen 
her begin her nest in the morning before any digger-wasp was astir, 
work several hours with diligence and then close the nest and fly 
away, perhaps not to return again for work until late the next 
afternoon after Bembex tex. had retired or was playing hide and 
seek among the nests of her colony. Carolina is, moreover, least 
susceptible to the influences of the weather; for, while other digger- 
wasps will lie listlessly about on.a cloudy day or sip nectar from the 
flowers, she may be as busy as ever. . 
Like the La Plata species, Monedula punctata, Monedula carolina 


28 Some Solitary Wasps of Tezas. 


lays a single egg in the empty nest and waits for the larva to hatch 
before she begins to lay in a supply of flies. This explains her 
leisurely behavior on the third and fourth days of the nest, when 
she digs spasmodically or even visits the nest without working at 
all. 

After the long and slender egg (six mm. in length) has hatched, 
the larva is kept well supplied with flies. These belong to any of the 
common species in the woods, Musca domestica, Calliphora vomito- 
ria and especially the large Volucella escurieus, Fabr. var. Mexicana, 
Macq. She does not confine herself to a single species of fly as does 
Thyreopus argus, which preys on a species of Dolichopus. The size 
of the fly is not graduated to the size of the larva, as is said to be 
the case with Bembex, but it appears that the first fly met with, large 
or small, is captured and brought home. The wasp carries the fly 
with her middle pair of legs and on entering passes it deftly back 
to the last pair. This habit seems to be characteristic of the Bem- 
becids in general. 

The larva is fed for at least eleven days; I observed one individual 
continue this from Aug. 17th to Aug. 28th. During this time, 
twenty-four or more flies had been brought in, since, when I dug 
up the nest, I found the large larva, (which spun its cocoon the 
next day) surrounded by the remains of empty dipterous skeletons: 
24 heads, 11 thoraces, 8 abdomens and many wings, the hardest 
parts of the different species of flies having been left. Fig 15 rep- 
resents a pupa surrounded by the remains of flies in the sand. 

M. carolina shows a remarkable variation in habit in that she 
sometimes closes her nest before she flies away, sometimes leaves it 
open and this applies to some individuals as well as to the species as 
a.whole. Of the eleven specimens that I observed, six closed the nest 
carefully each time they left it; two always left theirs open; two: 
closed theirs once or twice in a slip-shod manner leaving it open at 
all other times; and one closed hers carefully until she begun to car- 
ry in flies, when it was never again closed until the larva was full 
grown. - 

Each individual performs the final closure with scrupulous care, 
the whole tunnel being filled with sand and the surface smoothed 
over in the radius of a foot. One wasp kept returning to the nest 
occasionally for several days to throw more sand over the entrance 
to her old nest until she had kicked up a pile of sand three inches 
deep. 


Some Solitary Wasps of Texas. 29 


Monedula’s nest is the largest digger-wasp nest I know. The 
entrance, seen from above, has the form of an arch which measures 
about an inch across the base and three-fourths of an inch in height. 
Fig. 7 shows the wasp just crawling forth from her nest. The nest 
is a cylindrical tube more or less bent. It is three to five-eighths 
of an inch in diameter and runs down in a gentle slope for eighteen 
inches to a slight dilatation, the chamber, nine or ten inches below 
the surface. Fig. 21 is a photograph of a nest in section. It shows 
at about its middle point a rather abrupt turn to the left. 

If the nest has been closed, Monedula opens it without dropping 
her prey which she may happen to be carrying home. Ii the fly is 
accidentally dropped it is always discarded, even carried off to a 
distance and flung away. 

This fly-catcher, like the other fly-catchers of the family, stings 
to kill its victim. Every fly that I examined was dead, even those 
just brought home and dropped before the entrance. 


(z.) Nores ON THE STINGING Hasits or TACHYSPTEX TEXANUS, 
Cr., BEMBEX TEXANUS, Cr. AND NOTOGLOSSA 
(OXYBELUS) AMERICANA, Ros. 


It has been supposed of a number of fly-catchers that they pounce 
upon their victim in mid-air. This seems to have been the case with 
a specimen of 7’. teranus that come under my observation. I was 
busy working in the sand when I heard a light buzz at my right. 
Tachyptex was inflicting the death-sting on a fly of the domestic 
species, much larger than herself, and the two had dropped to the 
ground from above. Possibly the fly had been attacked while rest- 
Ing on a branch of a near-by tree but circumstances pointed rather 
to the conclusion that the struggle had begun with both on the 
wing. The fly lay helpless on its back and the wasp lay across the 
fly’s thorax curled around the left side with her sting fixed in the 
fly’s sternum. I placed the tow in a collecting-bottle with some sand, 
For two minutes the wasp held the fly impaled on her sting while 
she spent some time washing her face and antennae. She also 
walked around in the bottle, still carrying the fly, until she discov- 
ered that she was imprisoned, when she dropped her victim and flew 

excitedly around. 

_ This observation recalls Fabre’s assertion that Oxybelus carries 
home the flies impaled on the sting. The Peckhams, however, found 
that the wasp holds the fly with her hind legs and allows it to pro- 


‘30 7 Some Solitary Wasps of Texas. 


‘trude so far beyond the abdomen as to give it the appearance of be- 


ing attached to the sting. 
About the noon hour on a hot, sunny day, when the impiiaail to 
hunt is at its height, Bembex can.be seen following her favorite oc- 


‘eupation. One would suppose that where flies are most plentiful 


there the wasp would most often be seen. And this is found to bea 


“fact. The hunting and stinging habit of Bembex may readily be 
‘observed by watching a pile of horse-droppings near a Bembex col- 


ony. Flies collect and a wasp soon comes along to collect flies. 


‘She buzzes furiously about and the timid flies instinctively creep 


away as if to hide from their hereditary mortal enemy. The wasp 
makes a dozen or more circuits in the wildest zig-zag fashion darting 
again and again at flies on the dung-heap. Flights of this kind 
alternate with periods of rest on the sand near by, where the wasp 
stops to wash her face and smooth her wings while the motion of 
her abdomen betokens the rapid breathing occasioned by the stren- 
uous exercise. After a number of trials, usually many, Bember 


‘succeeds in pouncing on a fly. Quick as a flash the wasp is off for 


her nest with her victim. The operation is performed so quickly 
that it is utterly impossible to determine how the fly is captured 
and stung. I therefore captured a fly and pinned it down. Bembex 
returned, took hold of the fly with her legs and at the same time 
arched her abdomen under and stung the fly on the under surface 
of the thorax. The fly failing to yield to her efforts, the wasp im- 
mediately rose, caught sight of another fly and succeeded in cap- 
turing it. After a few moments she was back and attacked my fly as 


_ before. I then removed the pin. The wasp took up the dead fly four 
. times, rejecting it each time after having risen several feet in the air. 


It did not take her long to find out that there was something wrong 
with her capture. 
A wasp will return to the same hunting grounds until her larder 


is filled for the day. I have seen one wasp carry off as many as eight 


flies in quick succession. A number of times, too, I have amused 


- Inyself by allowing a wasp to take a dead fly from my hand, so that 


I could feel the active little creature as well as observe its every 


- mnovement. Two wasps of a species cannot agree to hunt together 


at the same place—they will quarrel in angry tones until one will 


- withdraw and priority seems, in st races, to be the claim usu- 
’ -ally recognized. 


But ‘the tiny black Notoglossa with her at tipped abdomen aa 


Some Solitary Wasps of Tezas. 31 


pay no attention to the big Bembex buzzing about. Though scarecly 
a quarter of an inch in length she hunts much like her comparatively 
gigantic congener. Her prey consists of gnats and other very small 
flies which she catches with greater facility than Bembdex catches 
her prey. I have seen Notoglossa texanus rest on horses’ feet and 
“loaf around” for hours, apparently on the lookout for her quarry. 
On one occasion I saw a tiny wasp appear repeatedly among a swarm 
-of gnats that had gathered around a sore on my horse’s ear. 


V. THE BUG-HUNTERS. 


(a) Brmsex BevLrracel, Cr., THE Bie Buc-HUNTER. 


Four times during the season I had the pleasure of observing in- 
dividuals of this interesting species at work. The species is rather 
a common one, and I should have observed more individuals had I 
had time. She is enjoyable company, for she does not object to one 
being near her. Her prey, however, I should think, might consist 
of a more inviting kind than the bug she captures, being stink- 
bugs at that. 

B. belfragei is one of the first solitary wasps I saw in the field 
and is chiefly responsible for inducing me to spend several weeks 
among them. I came upon the first specimen on July 16th at 9:12 
o'clock a. m. digging her nest in a wagon track. She had already 
made considerable progress in her work, for she seemed to bring the 
sand from some depth. She would remain out of sight for thirty to 
fifty seconds, then push up a load of sand and kick it out of the 
entrance. Fifteen to twenty seconds she would spend on the surface 
scattering the sand away from the entrance, as is more extensively 
the habit of Bembex tex. and Monedula carolina. When at work 
digging B. belfragei cuts about the same figure as B. texanus de- 
scribed above. The tibie and tarsi of the front legs with their long 
spines are used to scratch the sand and throw it back under the 
wasp’s body. Each time the head goes down, a single stroke of the 
leg is given and not several, as is the case with Bembex texanus. 

Once a Mutilled, five or six species of which are common in the 
woods, came running along the wagon-track, looked into the nest 
and greatly excited the owner, for the latter flew up with an angry 
buzz, darted at the intruder and put her to flight. 

At 11:40 the wasp began to interrupt her work by rising into 
the air, circling several times, settling some distance from the nest. 
and then returning to work. She repeated this three or four times; 
finally at 11:47 she came up from her nest, headforemost, instead of 
backwards, with sand, as she had been doing. She then closed up the 
entrance by scratching in sand until the entrance was covered flush 
with the surface and then flew away. After an absence of twenty- 
eight minutes, she returned and entered the nest without my seeing 


Some Solitary Wasps of Tezas. 33 


it, remained inside one minute and came out, closing the nest as 
before. This time she flew off without first circling about the nest. 

While the wasp was gone on the second hunting trip, a large 
Mutilled again came along, scratching at a great many places, here 
and there. Thus also she removed the sand from the entrance of 
the wasp’s nest, though she did not enter, but merely looked in and 
passed on. 

At 11:33 the wasp came back again with a large gray bug, alight- 
ing with it just in front of the entrance. I expected her to show some 
agitation at the disturbance made at her nest by the Mutilled; she 
appeared not to notice it, however, but holding the large bug with 
her middle pair of legs and balancing herself on her hind pair, 
she dug away some sand with her front pair. She then dropped 
the bug and crawled over it into the burrow. In a few moments 
she came up, head foremost, grasped the bug by an antenua with her 
mandible and drew him inside. In one and one-half minutes, she 
came out again, closed her nest carefully and flew away. 

During the afternoon belfraget came home without a bug. <A 
wagon had just came along and unfortunately cut away several 
inches of the burrow. Such a widespread disturbance in front of the 
nest would drive an ordinary wasp out of her wits. But this level- 
headed bug-catcher seemed, in spite of it, to know just where her 
nest was located and went to work clearing away the sand that had 
caved in. As she progressed, more and more sand fell from above and 
I assisted her by making an arch-way above with a piece of white 
paste-board to hold up the sand. Soon she had the nest open again 
and at 4:33 she flew away, this time leaving the nest open. 

At 8:25 on the following morning, wagon-wheels had again cov- 
ered up all the trace of the nest and belfragei was again in a quan- 
dary. Believing that she could not find her nest this time, I pro- 
ceeded to find it for her by cutting off slices of sand with a hoe in 
the direction of the nest until I came upon the tunnel four inches 
from the original entrance. All the time the wasp remained near 
the hoe like a playful kitten,—a remarkable performance for a 
wasp. She flew away before I had quite finished but returned in 
three minutes and went straight into the hole which I had prepared 
for her, resuming her work as though nothing had happened. 

At 8:42 the wasp flew away leaving the hole open. At 10:55 she 
had been back with a bug, which she took in as before, and had 
flown away after closing the nest behind her. This was the last 


34 Some Solitary Wasps of Texas. 


I saw of her. On July 21st, I returned to dig up the nest but failed 
to trace it. 

The individual whose actions were just described (No. 39) was 
the least sensitive to my presence of all the wasps I have known. 
Once I took her up in a bottle, and as soon as released she went on 
the even tenor of her ways. Other specimens I observed, while not 
annoyed at my presence, resented any movement on my part. They 
differed rather markedly also in the manner of their approach to 
the nest and of carrying their prey. 

My second example of B. belfragei having dug the nest completely 
in the forenoon, carried into it four bugs from 1:42 to 4:10. Hold- 
ing the bug venter uppermost with her middle pair of legs, the wasp 
would settle upon the sand that closed the entrance and stop there 
for nearly a. minute in a listening attitude. Perhaps she was get- 
ting her breath after the long flight with her burden, for her abdo- 
men would heave up and down after the manner insects have of 
breathing. At any rate, the delay in getting the bug under cover 
must be disadvantageous to the species for the reason that it gives 
parasitic or commensalistic flies more time to smell the bugs and find 
the nest. The habit is widespread within the species, for nearly all 
the individuals I saw act in this way. This hesitation at the en- 
trance forms a striking contrast to the habit of Rhopalum which 
dives into her open doorway. 

Assured that all is well, belfragei opens up the nest with her front 
legs, still holding the bug with her middle pair, and walks in. 
When just inside, she passes the bug back to the third pair of legs, 
or, dropping it, she advances until she can conveniently grasp it 
with the third pair. Then she picks it up again and passes on, 
the bug now projecting beyond the tip of the wasp’s abdomen. 

At 4:10 p. m. the last bug was brought in and the wasp began to 
permanently close the nest. After remaining inside for seven min- 
utes, she came forth scratching the sand back to fill up the tunnel, 
biting it loose from the sides, pulling it from the surface and press- 
ing it down with her abdomen. I caught her when she had nearly 
finished, and opened the nest. The tunnel, three-eighths of an inch 
in diameter and ten inches long, was entirely filled with sand and 
could be traced only by virtue of the dryness and the light color of 
the sand stuffed in. The pocket was one inch long and five-eighths 
inch in diameter and was five inches below the surface of the ground. 
It contained seven bugs. The egg was attached to the mesosternum 


Some Solitary Wasps of Tezas. 35 


of the bug and was directed forward so that it extended for a dis- 
tance along the proboscis (Fig. 14.) 

The bugs taken from the nest were all of the family of Lygaeidae. 
Of the seven, three kicked violently when touched and the remain- 
der showed some signs of life. After a day and a half three bugs 
were still alive, while the other four had just died. The former 
lived at least half a day longer. On Aug. 28th three large fly-mag- 
gots (Muscids) were crawling around the sand in the bottle as if 
trying to get out. The egg had disappeared. 

My third specimen (No. 46) came swooping down from the tree 
tops with her heavy burden. I have never seen the species out on 
the hunt, probably because she hunts altogether among the trees, 
the home of her prey. Each time No. 46 came home with a bug 
she descended out of the tree that overshadowed the nest. She car- 
ried in five bugs in two and a half hours, completing her labors at 
7:00 p. m., when she closed the nest. The nest was probably dug 
and provisioned on the same day (Aug. 27th), as was that of No. 
39, judging from the late hour at which the bugs were caught. I 
failed to trace the tunnel this time but came upon the chamber con- 
taining the bugs, which were all broad, gray ones of the genus 
Crytomenus, excepting one, a slender purplish bug belonging to the 
Lygaeidae. This latter was the first brought in and contained the 
egg which was attached in the identical manner as that of No. 39. 
If the egg was laid just after this first bug was carried in the length 
of the egg stage of this species is forty-one hours. The larva died 
after three days. Three bugs lieved two days; the other two were 
brought in dead. These bugs and the wasp’s egg are shown in Fig. 
14. 

The fourth and last specimen on which I have notes finished dig- 
ging her nest by 10:12, Aug. 31. As was the case with No. 1, she 
made a series of locality studies in preparation for her first depart-: 
ure by walking around on the sand in the neighborhood of her nest. 
At 10:12 she closed up the entrance carefully and flew away. At 1:00 
o’clock I returned to the nest, which was closed. At 1:27 the wasp 
returned, coming down out of the neighboring trees. She did not 
descend in a sudden continuous swoop, but in gentle jerks as if she 
were descending a flight of stairs and had to pause at each step to ad- 
just her load. This jerky motion goes on until she hovers over a 
bush two feet high standing between the wasp and the nest. Then 
she takes a sudden dive through an opening between the branches of 


36 Some Solitary Wasps of Tezas. 


the bush and lands on her nest. This strange mode of approach was 
used each time a bug was brought home, at 1:27, 2:17, 3:27, 4:41. 
It thus required over an hour for this individual to catch a bug as 
against one-half hour for the others. 

The chamber of this nest, which was closed like the others, was 
about the same dimensions as noted for the nest of No. 39. It con- 
tained five bugs, one of which was dead, three nearly dead and one 
so little paralyzed that it kicked spontaneously. Three of the bugs 
lived one day, while the lively one lived for five days. 

The egg had the conventional position on the sternum of a bug, 

but it was soon lost. A Muscid larva pupated on Sept. 3d and some 
Phorid pupae were also present in the bottle on Sept. 15th. 
- It is thus seen that Bembex belfragei displays a considerable 
amount of individual variation in general disposition, in the man- 
ner of approaching and leaving the nest, in the time required to dig 
and store it. The effect of her sting is also variable, the victim be- 
ing killed outright or living as long as five days. It may be said 
that this wasp is a novice in the art of stinging her prey, though she 
shows considerable more skill than Bembex texanus or Monedula 
carolina. 


(b) BrmsrpuLa Parata, Prov., AND BEMBIDULA PICTIFRONS, 
SMITH. 


Of these interesting and rather common species my notes show 
observations on only four individuals. From a study of their hab- 
its I concluded that I was dealing with a single species. However, 
No. 58 below was identified for me as B. parata and No. 48 as picti- 
frons; of the others I am in doubt. Since the habits of the two 
species agree so closely, I shall describe them as if they were really 
a single species. The wasps are smaller and stouter than Bembex 
belfragei, big bug-catcher, and the yellow bands on the abdomen and 
thorax are comparatively broader and more intensely yellow than 
those of the latter, so that as the wasps fly around the impression of 
yellow is the predominating one over that of black, the predominat- 
ing color of belfragei. 

Specimen No, 58 I observed from the time she was flying around 
in search of a suitable place to dig her nest up to the final closing. 
The wasp began digging at several places and finally chose the 
side of a shallow pit where only the day before I had dug up an 
Ammophila nest. The pit was six inches deep and the nest was 
begun three inches below the upper edge of one side. 


Some Solitary Wasps of Tezas. 37 


Bembidula digs much like the other members of her family al- 
ready described: Bembex, Microbembex and Monedula. During 
the progress of the work of digging the wasp makes short excursions, 
(on foot chiefly), around the neighborhood. Wasp No. 58 con- 
tinued digging for about two hours and at 12:30, when she had 
finished, she closed the entrance with sand. Before venturing away 
from her nest for the first time, she made a rather careful study of 
the locality, flying in and out among the herbs and bushes. In clos- 
ing her nest, No. 58 had more difficulty than her sisters because 
her nest opened on a sloping surface like a cave on the face of a 
precipice. In other cases, where the nest ran down from a level 
surface, there was left after closing a shallow elliptical depression 
like a gentle finger imprint almost characteristic of the species. I 
frequently made use of this depression to tell whether or not a wasp 
had visted her nest during my absence: I would smooth the entrance 
over and if the pit was visible on my return I had reason to believe 
that the wasp had come and gone. Bembecids as a rule are not 
easily disturbed by changes around their nests, as is the case with the 
Pompilidae to a high degree. In the case of the species under con- 
sideration, I often smoothed over the sand covering the entrance, 
but this in no way, as far as I could detect, disconcerted the wasp 
on her return. Sometimes I would, in addition, lay a blade of 
grass over the nest. The wasp would nevertheless find the nest im- 
mediately and merely kick the obstruction away. One individual, 
with a temper, once picked it up with her mandibles, carried it off 
to a distance and flung it angrily away. 

At 12:30 the nest of wasp No. 58, which I began to describe, 
was completed and the wasp had flown away. I was at the time 
trying to keep four nests of three different species under observa- 
tion and therefore failed to see this one enter her nest on her first 
return. 

At 3:07 she came back again and descended slowly toward the 
nest. When within three inches of the surface, she hovered an in- 
stant, then dropped suddenly like a dead-weight and after a mo- 
ment’s pause at the entrance opened it up and walked in. As she en- 
tered I could see her pass a very small bug back to her hind legs in so 
deft a manner as would do credit to a slight-of-hand performer. 
She remained inside but a minute, then came out, closing the nest 
behind her. In every case that came under my observation this 
species closed the nest thoroughly before flying away. On her re- 


38 Some Solitary Wasps of Tecas. 


turn she approaches cautiously and, when just over the nest, drops 
suddenly upon it. Moreover, she always carries the bug with her 
middle pair of legs and passes it back to the third pair on entering. 

At 3:39, the wasp was back again. Her manner of approach this 
time was quite different than before. Instead of flying directly 
down toward the nest, she flew back and forth above it in nearly 
parallel lines like a pendulum with ever shortening oscillations. 
This manner of approach she employed nearly every time. Other 
individuals of the species showed a habit approaching this, though 
not so marked. 

At 4:31, No. 58 came back again, but not straight to the nest. 
She flew around from bush to bush in the vicinity, hanging from 
the twigs a minute at a time. Once she allowed me to come close 
enough to see distinctly that she was hanging upside down by her 
first and third pairs of legs, while with her middle pair she clasped a 
small bug, holding it by its interior end, head directed forward. 
After thus “hanging around” for some minutes, she returned to the 
nest after her wonted manner. 

The next two days, Sept. 4th and 5th, were also spent in pro- 
curing provisions. The nights were not spent in the nest; this was 
carefully closed at the last departure in the afternoon and the night 
was spent in other parts. I have seen the species late in the eve- 
ning dig a shallow nest and crawl into it for the night, closing it 
from the inside, 

At 5:33 the wasp brought in her last bug. It was fourteen min- 
utes this time before she again made her appearance for the reason 
that she was now making the permanent closure of the nest after 
the manner of Bembex belfragei. After the burrow was filled with 
sand she scratched the sand all around the nest, even climbing to 
the top of the bank three inches above pulling down the sand. In 
this way all trace of the nest was obliterated. I immediately dug 
up the nest. Eighteen bugs were found in the lower, somewhat 
dilated end. There was no wasp egg or larva but three large 
fly-maggots were busy eating the store of food. 

Specimen No. 48 began digging her nest at 9:15 a. m., Aug. 31st 
and finished at 10:55. She, too, made an extensive locality study 
among the weeds in the vicinity, returning to the nest several times 
before flying away. She stored five bugs the first day. A parasitic 
fly, Masiena sp., kept hovering around the nest and twice, when the 
wasp returned with a bug, the fly flew up four feet or more to meet 


Some Solitary Wasps of Texas. 39 


the wasp and as the latter descended, gradually the fly flew back- 
ward ahead of the wasp, maintaining a distance of about three 
inches from her until the two reached the nest. After this was 
opened and the wasp had entered, the fly went in also and came out 
just ahead of the wasp. In the nest I found five bugs, one of which 
held the egg which was attached exactly like the egg of B. belfraget. 

No. 50 began digging her nest at 9:30, only five feet from that of 
No. 48, also on the same day. She stored her bugs in the afternoon 
of September 2nd. As the wasp had not visited the nest after 11 :20 
Sept. 2nd, I opened the nest at 8:00 a. m. Sept. 3rd and found a 
large larva among ten bugs, the viscera of most of which had 
already been eaten away. The nest is shown in Fig. 19. It was a 
compound curve sloping downward and toward the right for a dis- 
tance of eight inches. The pocket, four and one-half inches from 
the surface, was one-half inch in diameter and three-fourth inch in 
length. 

The larva began spinning its cocoon at 10:00 a. m. Sept. 5, i. e. 
on the fifth day after the egg was laid. It never quite finished spin- 
ning, though the pupa lived for ten days. 


(c) Hopxisorpes, Sp? 


This is a little brown wasp with yellow stripes, inconspicuous on 
account of its small size but of very energetic and business-like airs 
—like certain under-sized people. The species is rather rare, as I 
have seen only several specimens and but one actually at work on 
her nest. While I was standing in the shade, awaiting the return of 
several bug-catchers that had gone hunting, a Hoplisoides dropped 
down in front of me. She was carrying something which she let 
fall and immediately began digging for the entrance to her nest. 
She had evidently lost trace of this, for she dug at a number of 
places in vain. Bits of dried leaves and bark were strewn about and 
these were kicked away as though they were the cause of the wasp’s 
mistake, instead of being fit land-marks by which the wasp might 
have been guided and the mistake prevented. As it was, some min- 
utes were spent in finding and opening the nest. When this was done 
the wasp walked in. Assured that all was right, she came out and 
seized a piece of wood of the size and shape of the bug she had 
brought, rose on the wing to the height of a few inches, settled at 
the entrance again and walked in. I expected her to take in the 
bug lying in the entrance; but the piece of wood was carried in first 


40 Some Solitary Wasps of Tezas. 


and this I afterwards found in the chamber among the bugs of the 
wasp’s collection. She came out after this delay of a few minutes, 
seized the bug, rose on the wing after the usual manner, settled 
at the entrance and walked in with the bug, holding it under her 
abdomen with her middle legs. When only half inside the bug 
was dropped while the wasp crawled inside over it. After 14 minute 
the bug was pulled inside from within, as is occasionally done by 
Bembidula. In one-half minute the wasp came out, closed the 
nest and after making a few detours at the height of three to four 
feet, flew away. 

At 4:10 she came back again with another bug. This time also 
she encountered some difficulties in finding the entrance though 
there were many sticks and leaves about to guide her to the exact 
spot. Bembex or Microbembex or Ammophila never has so much 
trouble in getting into her nest even when there are no well recog- 
nized land-marks present to guide her. But instead of “making 
haste slowly,” this wasp loses time and energy in the hurry. She 
immediately begins to dig for the entrance after having dropped the 
bug, unlike Bembex, which continues to keep hold on the fly for some 
time while digging. After the nest has been opened, the bug is 
taken in exactly as before. In a minute the wasp comes out again 
backwards, scratching out sand, possibly some that had caved in. 
Finally she comes out head first scratching out sand, closing the 
entrance imperfectly, and flies away. By 4:51 she had come back 
again and was busy excavating the nest, scratching the sand with 
her forefeet and pushing it out with her abdomen. In this way 
she soon closed the entrance from within and remained inside one 
minute. At her appearance this time, she came out head foremost, 
scratching in sand as she came, after the fashion of the larger bug- 
catchers above described, when they are ready to close up the nest 
and leave it. This I supposed Hoplisoides to be doing in this in- 
stance and my suspicion proved to be wellfounded, because, when 
the nest was nearly filled with sand, the wasp began to carry into it 
bits of debris, that lay scattered about continuing at the same time 
to scratch in sand on top of them, like Ammophila is wont to do. 
While busy on the surface Hoplisoides holds her wings extended 
out obliquely like the social wasps. When held at a certain angle 
to the sun’s rays, the wings have a metallic blue lustre. 

Convinced that the work on the nest was nearing completion I 
caught the wasp and immediately dug up the nest and came upon 


Some Solitary Wasps of Texas. 41 


the chamber three-eighths inches in diameter and one-half inch 
long, five inches from the entrance and two and one-half inches 
below the surface of the soil. The passage from the entrance to the 
chamber was filled with sand and could be traced only near the 
ends. 

The chambers contained seven bugs, among which lay the above 
mentioned piece of wood as though the wasp had carried it in, sup- 
posing it to be a bug. The bugs were all nymphs of the same 
species, one of the family Membracidae. Three of the bugs re 
sponded to stimulation. The egg, 2 mm. in length was attached 
to the ventral surface of the bug close to and parallel to the mar 
gin of the thorax opposite the first and second pairs of legs. From 
its position I supposed this bug to be one of the last brought in. 

On September 4th, two days later two bugs responded to stimula- 
tion by a slight twitching. The egg looked dead on this day and 
finally withered. 


(d) Atyson MELLEus, Say. 


A. melleus is a slender wasp, less than half an inch long, in shape 
and size much like Agenia, the little spider-ravisher. Black is the 
predominating color of her body, her head, antenuae, tip of wings, 
and abdomen having that color, while her thorax and wings are red. 
She is, moreover, easily recognized by the pair of round white spots 
on the sides of her abdomen. She resembles the Agenia mentioned 
also in the easy grace with which she flits from place to place when 
on the hunt, which is mostly done on herbs and bushes. She runs 
swiftly up and down the stems and over the leaves, both the upper 
and the under sides, often darting like a flash to another branch or 
to another plant. 

The species must be rather common in the woods, for I have 
often seen her on the hunt and have several times seen her at 
work on her nest. She always selects the sloping sides of a pit as 
a location for her nest, at least I have never seen it at any other 
place. Fig. 24 is a photograph of the side of a pit perforated by 
holes dug by a number of species of Oxybelus, Alyson, Bembex, and 
others. There is an evident advantage to such a location over the 
usual position of a Bember nest, which runs down from a level sur- 
face, for Mutillids of various sizes, running around in great num- 
bers, never climb up a sloping surface to find the nests of digger- 
wasps. 


42 Some Solitary Wasps of Texas. 


The nest of melleus is always left open, day and night, which 
might give inquilines and parasitic flies a chance to get in. But 
the narrowness of the nest (two or three mm. in diameter) would 
keep out large flies and the great depth (12 inches) would tend to 
prevent smaller flies from finding the store of food. 

The excavation is carried out after the usual manner of wasps, 
the sand being loosened with the mandibles, scratched back with the 
forefeet and kicked out with the hind pair. The work of digging 
the nest is all done at once, though some dirt is brought up from 
time to time after the provisioning has been begun. 

My first specimen, No. 15, alighted in the bottom of the pit 
shown in Fig. 24 and walked over to her nest. It is the habit of 
the species to alight from three inches to a foot from the nest and 
then run over to it. No. 15 carried in her mandibles a small green 
leaf-hopper (Tettigonia bifida, Say). She entered the nest, re- 
mained inside a few seconds and was off again. She returned in 
three minutes with another leaf-hopper and made two more trips 
in seven minutes each by 5:19 p. m., when I left her. On my ar- 
rival at 10:00 the next morning she had been doing a little dig- 
ging. At 10:30 she came up to the entrance waving her long an- 
tennae at me and looked out. She then protruded her whole head, 
examined the weather and slowly crawled forth. Soon another 
individual was running around, evidently getting ready for the 
day’s hunt. This one was, however, destined to be shortlived, for 
she ventured too near a spider’s nest, whose owner, a perfect mimic 
of the sand, was lying in ambush. Quick as a flash the spider was 
upon the wasp, gave it a bite and as quickly returned to its lair. 
The wasp collapsed in the same instant. 

At 11:15 the first individual which I had been watching and 
which had returned into the nest, now came forth and, after mak- 
ing a locality study, was off. 

As a storm was approaching, I captured the wasp on her next 
return, eighteen minutes later and dug up the nest. I found it to 
extend downward in a gentle slope for a distance of twelve inches 
to a chamber of one-half inch in diameter. The chamber contained 
seven leaf-hoppers but no egg. 

Alyson oppositus is also common. It is somewhat smaller than 
A. melleus and shows its consanguinity to this species by the small 
round dot on each side of its abdomen as well as by its actions while 
on the hunt. 


Some Solitary Wasps of Texas. 43 
(e) RHopotuM (CRABRO) ABDOMINALE (Fox). 


This wasp is rather abundant in August and September. The 
sexes can be readily distinguished as they fly around the low vege- 
tation of the woods. The males have but one color, being wholly 
black, while the abdomen of the females is bright red in color. 
The thorax is very broad, which makes the abdomen, tapering grad- 
ually toward the pedicle as in the case of T’rypoxylon, look very 
narrow. &. abdominale reminds me of T'rypoxylon more than any 
other wasp in the manner of its flight, for both, while out hunting, 
are almost constantly on the wing and have a way of displaying 
their curiosity by touching with their antenne every leaf or stick 
or blade of grass in their path, 

Like Diodontus americanus, so well described by the Peckhams, 
abdominale has the habit of flying into her open door-way. It was 
this which first called my attention to her on September 14. The 
entrance to the wasp’s nest was a tiny hole in the middle of a small 
flat elevation in the sand. The wasp approached the nest from 
various sides, but whatever direction she came from, she first took 
up a position directly opposite the entrance to her nest, where she 
hovered for the twinkling of an eye,—just long enough to give me 
a glimpse of the green leaf-hopper, which protruded a little beyond 
her red abdomen. After this momentary quiver in front of the 
nest, abdominale takes a beautiful bee-line right into her open por- 
tal. It is a pretty sight to see this dive into the nest; it seems to 
indicate a wonderfully keen sight for an insect thus to see the 
tiny hole from the height of four or five inches and to judge her 
flight so truly. 

R. abdominale captures the same prey as Alyson melleus, leaf- 
hoppers of the species Tettigonia bifida, Say. She is a wasp of 
half the length of her competitor, but it takes her less time to catch 
her prey. On September 14th, she brought home seventeen to 
twenty leaf-hoppers, thirteen of which I saw carried in. The times 
at which this was done are as follows: 10:40, 10:55, 11:05, 11:20, 
Peep thas, 21 bd. 117) 1:50; 157, 2205, 2:09, 2:27. On 
each trip she remained inside but a few seconds. Her white sil- 
very face was the first to appear at the entrance. Here she waited 
but an instant before she was off like a flash, often so quickly that 
I did not notice the direction of her flight. 

Thyreopus (Crabro) argus shows the same haste in getting away 
from her nest and displays great acrobatic powers in the grace with 


44 Some Solitary Wasps of Tezas. 


which she slips into it on her return. Only once did abdominale 
hesitate a little, flying around the nest in a zig-zag manner, before 
leaving. The work on the nest was continued for at least three 
days, since two days were spent in storing alone. I failed to trace 
this nest, belonging to No. 67, but succeeded in tracing that of No. 
70. This went in nearly horizontally for two and a half inches 
and then down nearly vertically for four inches with a uniform 
diameter of two mm. The tunnel had a small pocket at the bottom 
containing a number of leaf-hoppers, but no eggs. 


Se 


VI. AGENIA, THE AMPUTATOR OF SPIDERS’ LEGS. 


(a) AGENIA, sP. Nov. AND AcEenra Accept, Cress., Two Dic- 
GERS. 


The species of Agenta are the most agile of all wasps not even 
excepting those of Pompilus and Aporus. The genus is unique in 
that its members, I believe without exception, have the habit of 
eutting off their victim’s legs. I have gotten glimpses of the do- 
ings of four species of Agenia; the two species first considered dig 
holes in the ground for their nests ; the other species, which are con- 
sidered separately below, build elliptical cells of mud in which to 
rear their young. Yet, though their nest-building habits differ so 
widely, their general appearance and their behavior when abroad in 
daylight make the genus easy of recognition. 

Agenia (sp. noy.) and Agenia accepta are very closely related 
both as to habits and structural characters. The latter is half 
again as large as the former, is darker in color and has clouded 
wings. Both species have made a strong impression on my mind 
because of their striking resemblance to the Texas red ant, Pogo- 
nomyrmex. The new and undescribed species I have seen only in 
the sandy woods on the river bank below Austin; A. accepta only 
on the limestone hills in and about the city. The same fact of 
distribution obtains for the common species of Pogonomyrmez; P. 
barbatus, so common everywhere else in the surrounding country, 
does not occur in the sand land where Poccidentalis, var. Comanche, 
with its disc-shaped mounds, is very common. These two species 
of ants differ markedly in color and somewhat in size, Comanche 
being the smaller and of a lighter hue. The same differences 
exactly exist between Agenia sp. nov, and accepta, the former, the 
smaller and lighter species, occurring only in the sandy tract above 
mentioned. While this may be a mere coincidence it is worth 
stating that most of the individuals which I have observed, were 
either near or in the midst of a lot of red ants, which they resemble 
respectively in size and color. Whether this be a real case of mim- 
icry or not, I would not say. But there is no doubt that the pro- 
tection afforded is considerable as the sting of the red ants is very 
formidable and a thing to be dreaded, while that of Agenia is weak 


46 Some Solitary Wasps of Texas. 


and can scarcely pierce one’s skin. The resemblance to the ant is 
moreover very much heightened by the transparency of the wings, 
by which these are rendered almost invisible. In fact, the first 
specimen I saw I at first did not distinguish from the dozens of 
ants in whose company it was running over the ground. My eye 
was attracted by a peculiar object lying on the ground, which proved 
to be a legless spider, and with so many ants running around, I 
knew that the spider could not have been lying there very long. 
Presently indeed, the wasp disclosed her identity by making several 
of her characteristic leaps of a foot or more from side to side, as 
she approached the spider. She grasped it by an anterior coxa and 
was about to make off with it, when, for lack of time to follow I 
captured her. The spider not only had all of the legs removed, 
but one of the palps as well. It was a large Epeirid, an immense 
load for the little wasp. 

The second specimen of this Agenia which came my way was the 
most skilful acrobatic performer I ever saw. She was carrying an 
Attid as long and much heavier than herself; but the load seemed 
a feather’s weight, for she carried it along so swiftly, so gracefully 
and with so little apparent exertion. She was carrying this spider 
in her mandibles and using her legs entirely for running up stems 
and over leaves. It was her method of progressing to climb the 
branches of weeds and bushes to their very tips, and then fly either 
across to another branch or onto the ground as far as she could. 
In this she resembled certain species of Pompilus, which, however, 
differ in climbing up stems and running on the ground backwards 
instead of forward. Every movement of Agenia was as certain as 
it was swift, for she never missed her aim in flying from branch 
to branch. Her descent even -was easy and graceful and she came to 
the ground as lightly as a feather. Thus for a time she chased 
on from bush to bush, climbing up the stems and descending to 
the other side. Suddenly our pleasure came to naught by the in- 
terposition of the suspending thread of an Agelina web. In these 
the two were caught, the Attid sticking fast and the wasp escaping. 
Nor did the wasp ever return, for I left the spider over night and 
during the next morning finding it still on the same spot the fol- 
lowing noon. The spider had all the legs cut off except the anterior 
right; the palpi were present. 

I have seen this species out hunting on several occasions and 
have found her to be a most thorough hunter. All her motions 


Some Solitary Wasps of Texas. 47 


betokened the greatest excitement. In her quick flight from place 
to place, she strikingly reminds one of Agenia accrpta, the second 
species, which darts around like her lighter cousin of the post-oak 
woods. I saw the first specimen on October 21st. Walking along 
the street, I chanced upon her as she dropped a large Attid among 
a stream of ants passing back and forth. She flew up as I drew 
near and I used the interval of her absence to examine the spider, 
which had all the legs amputated, though it was allowed to retain 
its palps. . 

Soon the wasp returned, grasped the spider by a coxal joint and 
carried it several feet further to the edge of a crevice in the ground. 
She then backed in, took hold of the spider and drew it down after 
her. Now came a test of patience which I failed to stand. After 
waiting three and three-fourths hours, I concluded that the wasp 
had escaped me, for I was used to quicker work of digging and 
storing a nest in sandy soil. I therefore dug down and found the 
crevice two inches deep, from the bottom of which the wasp had 
dug, almost vertically down, a nest one-fourth inch in diameter and 
three inches deep. Here I caught her, but failed to find the spider, 
which had possibly been left somewhere in the crevice. 

The other specimen I saw was again advancing with its spider 
where foraging ants were numerous. In fact, as I followed her, 
she suddenly disappeared with her victim in a deserted entrance to 
the ant-nest. In this case the spider, as far as I could make out, 
had lost but one of its appendages. 

It has not been my own good fortune to witness the amputation 
of a spider’s legs by an Agenia but I here report the observation 
of my friends Messrs. Julius Eggling and E. Jaeger on this opera- 
tion as it was related to me. A. accepta and her spider were the 
centre of the quarter hour’s excitement. ‘The spider, a large gray 
Attid, was resting on a fence post when the wasp flew at it and 
administered the sting. To tell just how this was done was ask- 
ing the observers too much. In an instant the victim was limp and 
helpless and the wasp immediately cut off one of the spider’s legs, 
the shreddy bark of the cedar post affording the wasp a pretty firm 
foothold. The spider thereupon fell to the ground but the wasp 
soon found it again and proceeded to carry it off. The spider’s 
legs, however, interfered with her walking, for, as I have observed 
above, Agenia straddles her victim and advances forwards. The 
wasp dropped her burden and set to work to cut off with her man- 


48 Some Solitary Wasps of Texas. 


dibles two more of the spider’s legs. ‘This was done very quickly; 
after one, two or three trials the leg snapped off like the end of a 
wire snaps off when a pair of nippers is applied. The spider was 
then taken up a second time but again set down owing to the inter- 
ference of the remaining legs. A few more legs were again nipped 
off and this process repeated a number of times until the legs were 
finally cut off all around, only the palpi of all the appendages being 
left. 


(b) Acrenta SupcortTicaLis (WALSH), AND AGENIA MELLIPES 
(Say). 


In contrast to A. accepta and her ally just considered, A. mel- 
lipes and subcorticalis have a sombre hue in perfect accord with 
the dark recesses where they build their adobe cells in secret. 
Mellipes is metallic blue, almost black in color and measures about 
three-eighths of an inch in length; subcorticales is somewhat larger 
and is distinguished by her red hind femora. 

My only acquaintance among the members of the species mellipes 
betrayed the location of her home by the directness of her advance 
toward it. Under a leaf on the ground in the angle formed by 
two roots of a large elm tree was the wasp’s nesting place and 
thither she was making trip after trip carrying pellets of mud for 
the construction of her nest. Like Alyson melleus, mellipes has the 
habit of alighting on the ground a little distance from the nest 
and covering this latter part of her journey on foot. She enters 
the archway that conceals her nest without hesitation but is more 
cautious on departure, looking out on the world and waving her 
long antenne before darting away on her errand. The wasp paid 
no attention to me; I was nothing to her, nor were, apparently, any 
of the other objects of her environment. For I took away some 
stems of poison ivy that obstructed my view and endangered 
my health; I even pushed back the leaf that covered the nest 
in order to observe her work—all this, without affecting her 
comings and goings in the least. Agenia was building her 
third cell; and since thirty to forty more trips are needed 
to complete each one, her familiarity with the surroundings finds 
an easy explanation. From 4:30 to 5:15, July 31, mellipes made 
fifteen trips requiring from one to five minutes each. ‘The little 
round pellets of mud which she carried home in her mandibles were 
added to the cylindrical wall until it had been built out to about 


Some Solitary Wasps of Tesas. 49 


the length of the wasp’s body. Fifteen to twenty seconds was suf- 
ficient time for the wasp to apply each load of mortar carried home. 
After the required length of the cell. which now looked a good deal 
like a barrel lying on its side, had been reached, the inside was 
earefully plastered and calcimined with a number of pellets of mud, 
the wasp reaching in for her whole length and at times working 
upside down. Possibly the wasp was adding an extra amount of 
saliva to this last work thereby manufacturing a kind of varnish 
with which to increase the durability of the structure. At any 
rate the interior presents a smooth surface while the exterior is very 
rough, each elevation representing the amount of mud brought in 
by a single load. 

At 5:15 the cell was ready to receive the spider with which it was 
to be stored. Mellipes, however, does not have good luck in find- 
ing the spiders she wants. On this occasion it took her twenty- 
four hours to store the cell, on another forty-six hours elapsed be- 
tween the completion and the storing. At 6:30 p. m., August 1, 
the wasp was just putting the finishing touches on the disc-shaped 
lid with which she closed the cell. I failed to catch the wasp at 
this time though I succeeded ten days later while she was at work 
under another leaf in the same angle of the elm tree roots. 

The wasp had built three barrel-shaped cells tapering slightly at 
both ends, each cell about eight mm. long and four in greatest 
diameter. One cell was independent of the other two which were 
built together at an angle of about 120 degrees. The angle seems 
to depend on the conditions under which the cells are built, for 1 
once found in a narrow crease of a wagon cloth five cells of mellipes 
attached one to the other in a straight line. Having reached home 
with my trophy I could not resist opening at least the cell last 
made to ascertain the condition of the spider and the position of 
the egg. Both are well shown in Fig. 20. The spider, it will be 
seen, had lost all its legs but the front pair and the egg was placed 
across the ventral surface of its abdomen. The spider was stuffed 
into the cell head first. 

But egg and spider were not the only occupants of the cell. To 
my great astonishment I became aware of a tiny parasitic wasp, 
no larger than Agenia’s egg itself, resting on the egg. The para- 
site (Ophelinus florifrons, Ashm.) had been imprisoned and when 
I found it, was evidently about to infect the egg of its host. It- 
had not yet laid its own eggs into that of melipes, however, for the 


50 Some Solitary Wasps of Texas. 


latter developed normally. It hatched and the larva in due time 
devoured every trace of the spider. August 8 it spun a fine white 
cocoon, which, it might be added, never changed its color. This is 
also true of the cocoons of A. subcorticalis. The larva succeeded in 
spinning its cocoon with support only from the low sides of the 
broken cell. It is also significant that the larva and pupa both 
developed quite as well in the light and without the protection of 
the mud cell, also in the dry atmosphere of the laboratory, as they 
would have done in their natural haunt on the banks of Waller 
Creek. The adult, a female, emerged August 23, just twenty-two 
days less three hours after the egg was laid. The adult from cell 
No. 2, also a female, emerged by a small round hole in the side of 
the cell on August 22 and the total length of its development was 
twenty-three days. On August 16, nineteen and one-half days after 
it was stored and closed, the oldest cell brought forth thirty to 
thirty-five parasitic wasps of the species mentioned above. Age- 
nia’s cocoon was present but its contents had been devoured by the 
larvae of the nefarious swarm which darted around on the inside 
of my collecting bottle clamoring for exit. 

My first acquaintance of the species A. subcorticalis was running 
along in a hop-step-and-jump fashion carrying in her mandibles a 
large legless Attid. She ran up a tree for a foot and dropped her 
burden to the ground. Before she could recover it another sub- 
corticalis was on the scene and a struggle for the spider ensued. 
The intruder caught it up and ran with it into a crevice in a tree 
as if to hide there. But the rightful owner recovered her quarry 
and made away with it in all haste, mounting a slender sapling to 
the height of twenty feet, and was lost to view. ‘The other wasp 
continued her search for a while but she too soon disappeared. 

Spiders are not the only creatures that will occupy the abandoned 
cells of an old mud-dauber’s nest. TJrypowvylon finds them a very 
convenient abode (Fig. 23) and even the graceful and handsome 
Agenia subcorticalis will not disdain to build her little cells and 
rear her young where an inferior Pelopoeus has been born. T'ry- 
poxylon uses the whole lumen of the empty cell as it is, merely 
closing the opening after the cell is stored. But Agenia uses the 
cells merely as cavities in which to build her own small cells of the 
ancestral type. Thus she may have as many as five of her own mud 
cells inside a single chamber of the big mud-dauber’s nest. In- 
deed subcorticalis goes a step farther and not only closes each one 


Some Solitary Wasps of Tezas. 51 


of her own individual cells but builds a plug over the opening to 
the large chamber just as the original proprietor would have done, 
thus offering an additional rampart to her enemies. 

The dirt which Agenia uses is taken from the very nest in which 
she is building her own. This makes it very convenient for her, 
of course. She gnaws off her pellets, moistening the dirt as she 
works. As I have observed in the case of T’rypoxylon the supply 
of water necessary for moistening so large an amount of dry dirt 
must soon give out. So after a number of trips Agenia, like 
Trypoxylon, flies away to get a drink of water and then returns 
to resume her work. She wisely economizes in her use of water 
by returning each time to the same spot, moistened by the previous 
visit, for each successive load. 

A considerable number of dirt-dauber’s nests were thus occupied 
by the new tenants. Owing to the lateness of the season many 
contained pup waiting in their clean white cocoons for the ad- 
vent of spring. Of the five spiders examined one remained in 
possession of all its appendages, one had the left hind one cut off, 
another had missing three hind legs on the right side, a fourth had 
only its front pair left and a fifth had lost all its legs. All the 
spiders were Attids of the same species. 

In each of the above cases of spiders deprived of legs, death had 
ensued even before the storing of the victim. I have, however, 
found mud cells containing mutillated spiders that were very much 
alive when found. In the spring of 1903, I found under the bark 
of an elm, a single cylindrical mud cell containing a young leg- 
less Attid that snugly filled the cell. This spider was alive and 
remained alive for at least a week. On October 21st, I found 
two cells under a stone, one of which contained a Clubionid, that 
lacked the hind pair of legs and the two anterior ones on the right 
side. It was not only alive, but would cling to a pencil held close 
to it and would bite at it. The spider remained alive until the 
larva began feeding. The egg was attached to the right side of 
the abdomen near the pedicil and there the larva on hatching at- 
tached itself and began eating. The pupa was spun November 
5th. 

The amputation habits of Agenia are interesting not only be- 
cause of the rareness of the habit among wasps, but because it 
seemed to have developed in this genus as the regular method of 
procedure. 


VII. SOME OTHER SPIDER RAVISHERS. 


(a) Pomprtus Marernatus, Say. 


This species of Pompilus has had its story well told by previous 
admirers. The single specimen, whose ways are here described, 
while agreeing in mental traits with her northern sisters, still, in 
my opinion, deserves a mention among her southern relatives to 
which these pages are devoted. 

August 2d was a fine, hot day and my early expectations of some 
interesting performances by my insect entertainers were fully rea- 
lized during the day. At 9:45, I came across a small Pompilus 
marginatus. The sprightly little spider ravisher alighted on the 
ground and hopped about in great agitation. I had often seen the 
species on the hunt and was anxious to see one in a duel with the 
eight-legged enemy of her race, or at work digging and storing the 
nest. She was at this time much more excited than when on the 
hunt; and she soon began to dig at a number of places only a few 
inches apart, showing that she was looking for a suitable place to 
dig her nest. After eight minutes of trial, she finally settled upon 
a place that seemed to suit her, little realizing, however, that she 
had chosen for the home of her offspring, the middle of a much 
used path through the sandy woods. Here she began to dig with 
vim and in a few minutes had dug a hole an inch or more in 
depth and was bringing out the sand at regular intervals, which 
increased in length with the increase in depth of the nest. The 
sand was pushed up in loads with the hind legs and the end of 
the abdomen. The wasp did not appear with a load each time, but 
often five or six loads would be allowed ot accumulate at the en- 
trance, when the whole pile would be pushed out and scattered 
.away from the entrance more or less carefully. All the work was 
done in feverish haste. While busy on the surface, the furious little 
worker held her wings straight up in the air, at times vibrating 
them and making them flash in the sunlight. 

Marginatus is a species that catches her prey before digging her 
nest and she did not delay long to make known where the spider 
was located. At 9:56, i. e., after the wasp had been digging but 
a minute, she left her nest and ran off among the grass and weeds 


Some Solitary Wasps of Texas. 53 


growing sparsely along the path. While running, the tiny worker 
betokened even more feverish excitement than when digging, for 
she ran swiftly with her wings standing out obliquely and in con- 
tinuous vibration, giving her a most comical appearance. Three 
feet from the nest the spider lay on top of a pinnatifid leaf of 
Achillia, excellently adapted to hold the spider and keep it out of 
reach of the many ants everywhere running around in great num- 
bers. (Fig. 5.) During the hour and eight minutes that it took 
to dig the nest (from 9:56 to 11:04), the wasp made six visits to 
the spider after intervals of one, five, nine, thirteen, thirteen, and 
thirteen minutes, each time returning to the nest in the same ex- 
cited manner. The visit was sometimes made partly on the wing, 
the wasp flying from one of the intervening plants to another. Her 
sense of direction was, however, not absolutely true, for only once 
did I see her go straight to the spider. Usually she passed it sev-- 
eral times before coming upon it. On the way back, the nest was 
found without much difficulty. 

At 11:04 the nest was apparently finished, for at this time the 
wasp ran over to the spider again, grasped it by one of the coxae 
and advanced with it to within fifteen inches of the nest, where she 
dropped it to reconnoitre the grcund and re-examine the nest. 
The next advance was to within one and one-half inches of the en- 
trance, when another survey had to be undertaken. The next spot 
was within an inch of the nest which was again examined. As- 
sured that all was right, the spider was once more picked up, and 
this time taken in. In being taken in, the spider first took a posi- 
tion with its long axis across the entrance; but the wasp, which 
had backed in, got hold of the posterior end of the spider and 
pulled it inside. It seemed to go in smoothly, though two of the 
legs were directed backwards. The wasp remained inside for fif- 
teen minutes and finally appeared scratching in sand and stepping 
it down into the nest. When this was nearly full, she pulled down 
the dry sand from above the entrance, biting it loose with her man- 
dibles. After a few minutes rest in the shady corner of a human 
foot-print, she returned, smoothed over the entrance for a moment 
or two in a wider circle than before and flew away. 

I immediately dug for the spider that had been just entombed 
and came across it four inches from the opening of the nest and 
three inches below the surface. It was lying in a chamber large 
enough to hold it with outstretched legs. 


54 Some Solitary Wasps of Texas. 


The egg, one mm. in length, was placed on the dorsolateral side 
of the abdomen near the pedicil, as shown in figure 12, which is 
natural size. The spider had been stung to death since it never 
responded to stimulation and was soon overtaken by mould. The 
egg never hatched. 


(b) PomprLocaster FuscIPpeNNIS (LEPEL). 


This wasp with black legs and thorax and bright red abdomen is 
a furious hunter, flying from plant to plant in a whirlwind. No 
wonder therefore that I lost sight of a specimen so suddenly one 
afternoon as she was carrying off her prey. ‘A flash of red and 
green is all I saw as wasp and spider tumbled down a hole in the 
sand and disappeared. The hole lead into a burrow that had been 
‘dug by some rodent and extended for many feet just beneath the 
surface of the sand. I have noticed other spider ravishers choose 
such a place to hide their spider and to dig their nest. Solid black 
soil, which cracks in dry weather, offers more opportunities in this 
way than does the sandy land where most of my observations were 
made. 
- The wasp remained inside the burrow one hour and twenty min- 
utes. Thinking that the wasp had by that time escaped at another 
point along the burrow, I dug this up and came upon the wasp, 
that had buried the spider in a shallow hole which it had dug in 
the side of the burrow. The spider, which was dead, was a large 
green “cotton spider” belonging to the genus. Dolomedes. The 
wasp remained in the vicinity for half an hour, when I caught her, 


(c) Pomprtip THat Does Nor Bury its Prey. 


‘In the Cambridge Natural History, vol. VI, p. 106, Sharp makes 
mention of Emery’s account of “some Pompilids that do not bury 
their prey but, after stinging it and depositing an egg, simply leave 
the spider on the spot.” Such an one came flying about our veranda 
with businesslike airs one fine July day. She was of a brilliant 
metallic blue, somewhat lighter than Pelopaeus coeruleus. She 
looked into eyery nook and cranny of the walls that struck her 
fancy. Finally she remained some little time behind a detached 
piéce of wallpaper from which the edge of a spider’s web protruded: 
Looking down I saw the wasp tugging away at a spider; but this 


Some Solitary Wasps of Texas. D5 


had its claws so thoroughly entangled in its web that the wasp was 
forced to desist. 

After stinging this spider the wasp spent five or six minutes 
flying about, resting on the rafters or running up and down the 
walls. At the end this time she disappeared behind the head- 
casing of a door where another spider had sperad its web. Pres- 
ently the wasp came forth dragging the spider backwards over its 
own web with her mandibles fastened to one of its front coxae. 
The spider was deposited a few inches below the edge of the casing 
on the margin of its own web and the egg laid upon it. At 3:07 
the wasp was out and flew airily about and in a minute was off 
and away. At 3:20 she returned to the first spider on which, after 
removing it, I found an egg. I can not say whether she laid the 
egg at the first or at the second visit. In either case it is certain 
that two eggs were laid in less than fifteen minutes. 

The first spider never showed any signs of life but soon withered. 
The egg died from an injury received in the handling. The sec- 
ond spider lived till half consumed by the larva. This spun its 
light cream-colored cocoon (which turned yellow in a few weeks) 
ten days after the egg was laid. Late in August the adult emerged 
by cutting and lifting a circular cap from one end of the cocoon 
after the manner of Ichneumon flies. This specimen was a male 
and it was therefore impossible to identify the species. 


(d) Muiscopuus Sp? 


Nearly all kinds and sizes of spiders have their wasp enemies, 
from the giant tarantula, which is hunted by the powerful Pepsis, 
down to the young spiderlings captured by Miscophus. This spe- 
cies is a tiny black wasp hardly four mm. in length but very active 
for her size and just as “bright” as any of her big sisters. 

She digs her nest with mandibles and forefeet like most digger- 
wasps. She is not particular about cleaning away the sand from 
in front of her nest for any great distance while she is busy dig- 
ging it, with the result that the sand kicked out collects in a semi- 
circle in front of the nest. When the nest is completed and ready 
for occupancy and, indeed, when it is left temporarily, it is usu- 
ally carefully closed with sand and the surface in a radius of sev- 
eral inches is often smoothed over in a neat and tidy manner. She 
is extremely sensitive to one’s presence. When she is carrying a 


56 Some Solitary Wasps of Texas. 


spider, a slight motion on my part will make her drop her burden 
and fly away for a minute or two. 

Miscophus catches for her prey young Epeirids of convenient size. 
These are carried home on the wing if very minute; medium-sized 
ones are carried in small jumps like the crickets of Larra, the length 
of the jump depending on the weight of the burden; larger spiders 
are carried on foot. I have seen no Pompilid carry her spider 
quite like Miscophus. ‘This wasp grasps the paralyzed spider with 
her mandibles by two or more of its legs, “slings it on her back” 
and marches off with it, walking forward, the spider hanging rather 
to one side in an uncomfortable and awkward looking manner. 
Arrived at the nest, the wasp opens it, enters and drags her prey 
after her. After the nest has been stored and the egg laid, the 
tunnel is closed with sand and the surface smoothed over with 
fastidious care. 

I opened two nests each of which contained six spiderlings, the 
largest in each nest having attached to its abdomen near the pedicle 
a minute egg. I did not succeed in rearing any adults for each of 
the two larvae died after having lived a larval life of five days and 
spun an incomplete cocoon. 

The nests were astonishingly small. The first had a tube two 
mm. in diameter leading slantingly downwards for a distance of 
three centimeters to a pocket measuring five mm. across. The other 
nest was dug in a small clump of dirt which was itself hardly three 
centimeters in greatest length. The nest measured but fifteen mm. 
(% inch) in length including the round pocket, five mm. in dia- 
meter, which harbored the spiders. 

. Miscophus, though the smallest in size among the spider hunters, 
is not least in interest nor does she hold a place in my esteem pro- 
portionate to her size. 


VIII. TRYPOXYLON TEXENSE (SOUSS), A PET OF THE 
HOUSEHOLD. 


Several species of T’ryporylon have been admirably described by 
Mr. and Mrs. Peckham in their delightful book already frequently 
referred to. JI would not presume to attempt to improve in any 
way on their account of this so well “domesticated” genus; yet I 
hope that the few new observations here presented on the Texas 
species may be of interest to the reader. 


The many scattered notes J have made on the doings of 7’. texense 
agree in essentials with the observations set forth in the work just 
cited. In disposition the southern species is also amiable and good 
tempered and is most tolerant of the actions which curiosity prompts 
the observer to take, up to the point of destroying the nest itself. 
The male of texense, when present, remains faithfully on guard in 
the nest during the absence of the female. I have found a large 
proportion of the nests without males; in such cases the female 
went on with her household duties as well as when joined by her 
vespine consort. In one case a male remained alternately on guard 
in two contiguous nests; when both females returned at once the 
male exhibited more than the usual amount of excitement in spite 
of the fact that neither female paid any attention to him. On the 
presence of the male in the nest of these wasps I shall perhaps in a 
later paper have more to say, for I believe the subject worthy of 
further investigation. 

In the selection of a nidus texense exhibits the same habits as 
rubrocinctum, occupying almost any small crevices in wooden or 
stone walls. Beetle burrows in the cedar posts of log cabins along 
the Colorado River are nearly all occupied by T. texense. Fig. 23 
represents a pair of these wasps occupying a cell of an old mud- 
dauber’s nest. I have found it very convenient to attract the wasps 
by setting out for them blocks of wood with holes bored in them. 
The wasps will make use of borings one-half inch in diameter but 
prefer tubes of smaller calibre. It does not seem to make much 
difference whether the tube is horizontal or vertical, both condi- 
tions being acceptable. I have found several two-story nests in 


58 Some Solitary Wasps of Tezas. 


empty shot-gun shells standing upright. In these the partition 
and the plug were each in two layers, an inner of white and an 
outer of yellow clay, each layer being a millimeter in thickness. 
In getting the nest ready the only thing I have seen texense do is 
to plaster a few pellets of mud against the bottom of the tube. 
Thus the cap hole of the shot-gun shell was tightly closed with it. 
The length of the chambers depends on their calibre and varies 
from three-fourth inch to one and one-half inches. When a nest 
is composed of several cells in horizontal series, the partition is 
built from the bottom up and is therefore thickest at the bottom. 
In closing the last chamber an extra amount of mud is plastered 
on and the plug is brought flush with the surface. In about half 
the cases the final closure was made with two plugs from one-fourth 
to one-half inch apart leaving an empty space or false chamber be- 
tween them. This must certainly be an effective means of de- 
ceiving such: parasitic enemies (should they have any) as lay their 
eggs by means of boring ovipositors into the nests of their aculeate 
hosts. 


IT. texense has a way, as I have already pointed out above, 
in connection with Agenia subcorticalis, of economizing time in the 
matter of getting mortar for the nest. I had always thought that 
this was gotten from the moist banks of the creek or river, whither 
Pelopaeus pilgrimizes for her building material. But it is certain 
that many do not get mud from that source but instead take it 
from the nearest place obtainable, namely those great pyramids of 
the world of wasps, the abandoned mud-dauber’s nests just at hand. 
Soon after I had begun inducing texense to make her home with 
us and build her nests on the gallery of the Lucksinger country 
home, the old mud-dauber nests began to decrease perceptibly in 
size, their material being used again in similar architectural enter- 
prises. Trypoxylon flies from her nest to a suitable place on a 
mud-dauber’s nests and begins to gnaw off a piece of the dirt with 
her mandibles moistening it with saliva as she works. Pelopaeus’ 
old house is hard and one can hear the grating and clicking of 
Trypozylon’s mandibles upon it as well as the hum of her wings 
under the strain of her work. Finally a pellet as large as her head 
is loosened and the wasp, just as the pellet is ready to drop, catches 
it “under her chin,” as it were, and takes it to her nest. The dirt 
is moist when plastered on and one can’ see the’moist spot from 


Some Solitary Wasps of Tezas, 59 


which a wad of it has just been taken. To this same spot the wasp 
returns for successive loads, thus economizing in the expenditure 
of saliva necessary to wet the dirt. This requires, of course, more 
moisture, even for a single partition, than the wasp’s body can well 
hold and it becomes necessary to replenish the stock at intervals. 
So I have noticed that after every four or five loads the wasp flies 
away in the direction of the creek, seventy-five yards distant, pre- 
sumably for a drink, and returns to continue her work where she 
left off. 

Like T. rubrocinctum a day’s work with texense consists of at 
least storing and closing one cell, though two cells a day is not un- 
usual for her. Of those individuals on which I have detailed notes 
one stored two cells in one day and one cell the next forenoon, two 
others each two cells in one day, one stored nine Attids, one Tho- 
misid and three Epeireds and closed the nest all in three and one- 
half hours; another stored and partitioned off one cell in eight 
hours and stored and plugged up the second cell in ten hours. 
Thus texense is more industrious than rubrocinctum, which shows 
that a semi-tropical climate is not enervating to the wasp race at 
least. 

The development of the young wasp is more rapid in the Texas 
species than in the northern. The period required for the egg and 
larval stages of texense together varies from six and one-fourth to 
seven days and averages nearly seven days. One larva spun its 
cocoon in five and one-half days but never reached the imago stage. 
The length of the pupal period is a little more or less than thirty 
days. 

T. texense captures eight to twenty-five spiders for a single cell, 
the average being about fifteen. When a nest is composed of two 
superposed or adjoining cells the deeper one or the one first stored 
has invariably the greater number of spiders; the difference is 
specially noticeable when both cells have been stored the same day. 
The wasps seem to have a decided sense of fatigue, which is quite 
natural. The great majority of the spiders are alive when brought 
in; the majority of these live to about the third day. This accords 
with the findings of the Milwaukee students in the case of 7’. ru- 
brocinctum. 

T. texense begins work early in the year and is on the crest of 
her presperity at the time rubrocinctum, her northern cousin, is 


60 Some Solitary Wasps of Texas. 


“losing interest in the family affairs and taking a well-earned holi- 
day on the blossoms of the aster and the goldenrod.” Tezense is 
our most common solitary wasp next to the red Pelopaeus, among 
which she may be seen at work, the former decorating(?) the wall 
with her edifices, the latter modestly occupying the out-of-the-way 
crannies and crevices that might otherwise be used by spiders as 
their retreats. 


IX. SOME ENEMIES OF THE ORTHOPTERA. 


(a) Larra AMERICANA (FOX), AND HER CRICKETS. 


The first specimen of this species which I chanced upon was dig- 
ging her nest on the edge of a small precipice at the bottom of 
which lay three crickets, all kicking violently, one even almost able 
to crawl away. Her manner of digging was peculiar among the 
solitary wasps I have seen. While she proceeded in part by scratch- 
mg the dirt back under her much like Pompilus and with equal 
vigor and nervousness, she pushed out the loads she accumulated 
in a different manner. Other wasps use chiefly their hind legs and 
abdomen; but this specimen used her head and front legs, im- 
provising of these a kind of scraper. To take on a load of sand 
the wasp stretched out her legs, lay down flat and pushed her head 
in the sand and backed out. On account of this method of digging, 
the burrow resulting was wide and low, so as to make room for the 
outstretched legs. 

There was something wrong with this individual of L. Amer- 
icana. She soon lost interest in her work, ran around looking into 
other nests and other holes in the ground. She acted in a most 
demented manner. Her visits to her old nests and to her crickets 
became fewer and fewer and she finally remained away altogether. 

My second specimen I followed to her nest on the nearly vertical 
bank of a creek near Austin. She was carrying a large cricket in 
her mandibles and was moving along in jumps of a yard or more. 
She alighted at the bottom of the embankment and walked up its 
steep side entering a large hole, from the further end of which she 
had dug her nest. In this way I saw her carry in four crickets 
of various sizes. ‘Two days later I found the nest closed with earth, 
though not quite to its mouth. I dug up this nest as well as another 
close by and found both to have been of about the same shape and 
dimensions. A tunnel five-sixteenths inch in diameter ran into the 
embankment at a slight inclination downward for a distance of 
four inches. It ended in a dilatation, one of the pockets of the 
nest. Just in front of this the tunnel branched off for a slight dis- 
tance and lead into another pocket which was the larger as well 


62 Some Solitary Wasps of Texas. 


as the one first made. In this six crickets had been stored, all of 
which but one (which was dead) were not only alive but positively 
lively. One, indeed, after I had dug out the nest, very nearly got 
away from me. The smaller pocket contained but one large and 
one small cricket, both very much alive. The larva in each case 
had attached itself to the prosternum of the most active cricket and 
curved around the body of its host, thus embracing it for better 
protection. Larval americana does not eat any of the hard parts 
of its viand, but reaches into the thorax, abdomen, head and legs 
to procure the meat and suck the juices. After five days the older 
larva (ca. six days old) had devoured its store of food while the 
other had eaten but one large cricket. Both spun an imperfect 
cocoon and soon died. 

Tachytes abductus (Fox), var.? is a rather common Larrid in 
this locality. The wasp is black and in the sunlight there is a 
shimmer of bronze between the segments of the abdomen. The 
species catches nymphal short horned grasshoppers, carrying them 
closely pressed to her venter with her legs. She is to be admired 
for the reluctance with which she betrays the whereabouts of her 
nest, 


(b) Priononyx THoMAE (FAsRE), THE Locust KILLER. 


As late as October 9th, after her northern cousins had begun to 
lose interest in the affairs of life, Priononyx Thomae was as busy 
as ever. My only specimen of this interesting wasp flew up from 
her nest as J came down the well-worn path where she was at 
work. A flash of red was all I saw at first; from this and from 
the shape of the nest on which she was engaged, being a round hole 
leading straight down, I was led to believe that the creature I had 
disturbed was none other than Ammophila. Priononyx soon re- 
turned, however, and proved that she was an entirely new acquaint- 
ance, though her subsequent actions clearly showed that both she 
and Ammophila had inherited mental traits from the same not 
very distant ancestors. She is more stoutly built than A. procera, 
is smaller and is black with the exception of her abdomen which is 
bright red in color. 

A faster worker never lived than P. Tomae. But her speed 
is due to a deliberate haste and not to the insane, wasteful hurry that 
seems to characterize the actions of many species of Pompilus. At 
1:30 she returned to her burrow which she had dug down to the 


Some Solitary Wasps of Tezas. 63 


length of her body. After working at it for a minute she aban- 
doned the nest for some reason, filled it with sand to the top and 
started a new one near by. Although digging in a well-worn gray- 
elly pathway she made astonishing progress. Biting the pebbles 
and smaller sand grains loose with her powerful jaws she scratched 
the loose material out with her fore-feet or carried the larger pieces 
out with her mandibles. Her movements had almost machine-like 
regularity, entering the nest forwards and invariably backing out. 
Back and forth she went, darting in and out so quickly and smoothly 
that I can best compare her movements to those of a rubber ball at- 
tached to the end of an elastic band. After thus working for 
nineteen minutes, Priononyx flew away to a distance of twenty feet 
where she pulled forth a large green locust. Straddling her prey 
like Ammophila and grasping one of the short antennae she ran 
swiftly down the path. Within two feet of her nest she carried the 
grasshopper into a tuft of grass, which she easily mounted with her 
burden thanks to the length and the strength of her legs. After 
then digging at her nest for five minutes more she took up her vic- 
tim as before and carried it over to her nest, laying it down with its 
head near the entrance. She then, like Ammophila again, backed 
down the tunnel and pulled the locust after her. In a minute she 
reappeared and immediately began to close the tunnel. Scratching 
in pebbles and dust, she tamped them down with her head. I now 
placed a net over her but she worked complacently on. I could 
see her every action through the thin net, for she worked but a 
foot below my eyes. After the net was full flush with the surface 
good sized pebbles were carried over it. Time and again these were 
tightly grasped in her mandibles and pressed down with might and 
main, the wasp standing the while straight on her head and almost 
turning a summersault while her busy buzz indicated the exertion 
which the operation demanded. Then she dug awhile in the aban- 
doned hole she had previously filled in but soon quit digging and 
filled it in a second time. [I slightly raised the net and Priononyz 
flew away. 

An hour later she was again at work only a few inches from the 
scene of her previous operations, digging another nest. Three feet 
away I found another green locust under a clump of grass—an- 
other prey for another nest. Thus it seems certain that Thomae 
first catches her prey and then digs her nest. At this juncture I 
caught her. 


64 Some Solitary Wasps of Tezas. 


The greatest surprise was, however, yet in store for me. With a 
pick axe I dug a hole about a foot deep at a safe distance from the 
nest and with a trowel worked away the hard earth carefully in the 
direction of the nest so as to lay it open and yet not injure the 
grasshopper or the egg upon it. To my surprise I came upon a nest 
sooner than I had expected; to my still greater surprise the grass- 
hopper had not an egg but a good-sized larva upon it. A second nest 
was then revealed and a third and so on until eight had been opened 
and I had lying before me a collection of nine caterpillars, including 
the one not yet stored. All the nests were scattered over a space not 
larger than half of this page. The chamber was oblong (long axis 
horizontal), about two inches in length by 14 to 7% inch across and 
two inches below the surface. Some of the chambers were so close 
that they had but a 14 inch wall between them. Just at what point 
the tunnel (which measured %% inch in diameter) entered the cham- 
ber, I could not exactly determine but think that it come off of one 
end, which would make the shape of Thomae’s nest nearly like that 
of Ammophila procera. (Fig. 22.) 

In each case the egg or larva had an exactly similar position on 
the locust. This was just above the coxa of the hind leg (which in 
one case was torn away) i. e., between the articulation of the coxa 
and the locust’s “ear.” The only variation in this regard was that 
in four cases the egg or larva was placed on the right and in four 
on the left side of the locust. 

The egg of P. Thomae is slender and about 7 mm. in length. It 
arches from its point of attachment over the coxa of the hind leg, 
which, though the free end of the egg touches it, cannot easily in- 
jure it no matter how much the locust may be kicking. The egg is 
yellow with the exception of the two hyaline ends. Its anterior 
third is white and the extreme attached end is a watery hyaline 
disc. Like the egg of Ammophila, that of Priononyx does not 
seem to hatch. The first indication I perceived of larval life was 
the appearance of tracheal tubes down each side and later the suck- 
ing movements on the inside of the translucent larva. 

Below I give the data on the condition of the nine locusts found 
Oct. 9th and the development of the larva: 

No. 1.—Locust not yet stored. Dead when found. 

No. 2.—Locust kicks violently without stimulation. On touching, 
it will jump two feet. Egg dead. Locust lived four days. 

No. 3.—Locust twitched spontaneously from time to time as long 


Some Solitary Wasps of Teas. 65 


as Oct. 11; leys and mouth parts do not usually twitch simultan- 
eously. Egg was the one most recently laid (Oct. 9). Larva spun 
cocoon in night of Oct 14-15. Length of larval life 514 days. Co- 
coon soon turned dark brown. 

No. 4.—Locust a great kicker; jumped three feet with egg upon 
it ; lived till Oct. 11, when wasp grub was nearly half grown. Very 
young larva showed trachee when found (Oct. 9); begun to spin 
cocoon at noon Oct. 14; cocoon light brown next morning. 

No. 5.—Locust kicked violently when irritated as long as Oct. 10 
though larva was 7 mm. long and half as thick. (The larva after a 
few days is shorter, though very much thicker, than the egg when 
jaid). Larva spun cocoon a. m. Oct. 13. 

No. 6—Same as No. 5. 

No. 7.—Very small locust was dead when found for larva was 
itself nearly as large as its victim; locust devoured Oct. 11; very 
small cocoon spun Oct. 12. 

No. 8.—Large locust dead; large larva reaching into thorax. Co- 
coon spun a. m. Oct. 13. 

No. 9.—Locust dead; devoured Oct. 11. Oct. 12 larva tried to 
spin cocoon but failed and died. 

From these data it would seem that there were three sets of grass- 
hoppers according to the age of the eggs or larve upon them. The 
facts go to show that the first three were captured Oct. 9. No. 4 
might possibly also have been captured and stored early the same 
day, though more probably late the day before; Nos. 5 and 6 were 
certainly stored Oct. 8th. Nos. 7, 8 and 9 were stored Oct. 7. Thus 
this P. Thomae accomplished the feat of digging in hard soil and 
provisioning three nests a day for three days in succession. It is 
also significant that all these nests were made in such close proxim- 
ity. The locusts were all of the same species and were, in all cases 
but one, I have reason to believe, entombed alive and lived until 
killed by the wasp-larvae themselves. 

In many of her ways Priononyx Thomae reminds one of Ammo- 
phila in her general demeanor; in running in and out of her nest 
while engaged in its excavation; in the shape of her nest; in the 
manner of carrying her prey, in laying it down at the entrance and 
backing inside to pull it after her; in closing the nest and pressing 
pebbles down upon it as if to add some finishing touches intended to 
be ornamental as well as useful. 


X. EXPERIMENT ON THE SENSE OF DIRECTION OF CER- 
CERIS FUMIPENNUS. 


The Sense of Direction of animals, particularly of Ants, Bees, 
and Wasps, is a subject which has engaged the attention of many 
naturalists. From my own observations on social and solitary wasps 
I incline to the opinion that these are guided mainly by sight in 
which familiar objects in the environment of their nests are im- 
portant factors. 

A rather decisive evidence of the important role played by trees, 
bushes and other objects in the orientation of insects is afforded by 
the actions of one of my friends, Cerceris fumipennis. On October 
24th I discovered her bearing a weevil (Chonotrachelus neocrataege) 
into her nest, which was situated on the edge of a five-foot embank- 
ment just under a bush some two feet high. The next day I re- 
turned, cut the bush off at the roots and placed it three feet to the 
right. Soon fumipennis, too, returned and flew, not to her nest 
but to the bush which I had placed to one side. After discovering 
her mistake she flew away to get another start, came down again 
from between two trees and flew to the bush. Since she repeated 
this performance at least a dozen times without finding the nest, it 
is safe to conclude that it was the bush which directed her flight. 
Moreover, the wasp always flew down from the same direction, show- 
ing that earlier in her course she was directed by other objects, es- 
pecially trees. This latter observation I have several times made 
on wasps whose nests I destroyed before the owners had completely 
stored them. é 

As a matter of fact, the power of finding their way is not so per- 
fect as one might be led to suppose. Many spider-ravishers have 
great difficulty in finding the spiders which they hid or hung up 
while digging their nests. I have seen individuals of Bembex tex- 
anus and Monedula carolina so far lose track of their nests as to 
fail entirely to find them again. 

In view of these and other facts I should agree with the Peckhams 
in the opinion that wasps have no additional sense, the sense of di- 
rection, in the common acception of the term, nor that they find 
their way by a process of dead reckoning as Darwin suggested, but 
that they find their way by a detailed familiarity with objects near 
the nest and by a general acquaintance with the locality in which 
they pass their lives, 


SUMMARY AND CONCLUSIONS. 


The present paper comprises more or less detailed observations - 
on some 28 species of Texas Solitary Wasps. It was not written 
for the purpose of entering the discussion of mooted questions of 
instinct and intelligence, but rather of describing clearly and ac- 
curately the actions of some of these delightful little workers in 
their natural haunts. 

My experiments on the mental faculties of wasps have been few 
and therefore of little value. The experiment recorded above on 
the sense of direction I have considered of sufficient value to be put 
down. It certainly has to commend it an absence of artificiality 
having been made by merely varying the natural conditions to which 
the wasp was already accustomed. In general my observations lead 
me to accord with the opinion held by the Peckhams and others that 
wasps are guided by sight in finding their way—by sight and the 
memory of familiar landmarks in the neighborhood. 

Of the varibility of instincts within a given species there can in 
my opinion be no doubt. The variability in mental traits and dis- 
positions as reflected in the wasp’s actions, seems moreover to be pro- 
portionate to the physicial variability. At any rate, Bembex bel- 
fraegi, the species of Bembidula and Microbembex monodonta for 
example are all very variable species in size and coloration as well 
as in the demeanor of different individuals. 

All the species of solitary wasps either dig holes in the ground 
for their nests or work with mud in their architectural pursuits. In 
the case of Agenia (Chap. VI) both kinds of nests are found in the 
same genus, some species digging typical nests in the ground while 
others build mud cells in protected places. This fact alone, it seems 
to me, would justify the setting-up of a distinct genus, Pseudagenia, 
as is done by some authorities. Among the wasps that dig their 
nests we may recognize two methods of excavation: in one the wasp 
utilizes the forelegs to scrape out the dirt loosened by the mandibles ; 
-in the other the wasp employs the mandibles both as pick and as 
shovel. Ammophila (Chap. I1) and Priononyx (Chap. IX) repre- 
sent the latter method and their nests are composed of a vertical 
tunnel leading straight down from the surface (Fig. 8) to a pocket 
whose long axis lies horizontal (Figs. 18 and 22.) The wasps work- 


68 Some Solitary Wasps of Texas. 


ing by the scratching method and employing their forefeet as rakes 
in excavation have simple nests consisting of a tube running ob- 
liquely down and ending in a dilation or pocket at the lower end of 
greater or lesser diameter (Figs. 19 and 21.) Among the mud- 
plastering wasps we may distinguish two methods of work again: 
Some species build the entire nest of mud, as for example Agenia, 
Pelopaeus, while others occupy convenient crevices, and use the mud- 
mortar merely to close the mouth of their ready made nests, as ob- 
tains in the case of Trypoxylon. The same genus may have species 
some of which practice the one, some the other method (Odynerus, 
Chap. 1). And again the same species, as Agenia subcorticalis 
seems to do, may combine the two methods, for she builds complete 
cells of mud not in the open air like Pelopatus but hidden away 
in crevices. 

Some wasps always carry their prey on the wing and on their re- 
turn to the nest alight directly in or over its entrance. Bembez, 
Monedula, Bembidula, Hoplisoides, Microbembex carry their prey 
with their middle pair of legs and press it closely to their venter ; 
Rhopalum abdominale and Notoglossa use their hind pair; Ody- 
nerus, Trypoxylon and Cerceris carry theirs with their mandibles 
as does also Alyson, which alights some distance from the west and 
completes her journey on foot. Larra americana and Microbembex 
prefer flying to walking; but when the weight is great the advance 
is in jumps or short flights, the distance of each advance being in- 
versely proportionate to the weight of the burden. 

Other wasps always drag the victim over the ground regardless 
of how light this may be and how absurd it may look (to us). Am- 
mophila’s method, to which that of Priononyx corresponds, is shown 
in Fig. 16. Some spider catchers (Miscophus, Agenia) walk for- 
ward in dragging their prey; others (some species of Pompilus and 
Pompilogaster) always walk backward. Agenia and some others 
combine the flying and the walking means of progression. These 
drag their victims over the ground, climb up the stems of herbs and 
bushes in their path and fly off, parachute-fashion, from the highest 
‘point obtainable in the direction of their course. The species dif- 
fer greatly, too, in the ease or reluctance with which they betray the 
locality of their nest, Miscophus and Tachytes abductus being, for 
example, experts in leading the observer astray. 

By the way in which a wasp enters the nest the species may often 
be recognized. Bembecids as a rule, after having opened the nest 


Some Solitary Wasps of Tezas. 69 


and on entering it, head foremost, deftly pass their prey back from 
the middle to the hind pair of legs. Microbembex, for example, 
never fails to do this regardless of the size, weight, or shape of the 
prey. Ammophila, like Priononyx Thomae, lays her victim down 
beside the entrance, backs down and drags it into the nest. Rho- 
palum (Crabro) abdominale and Thyreopus (Crabro) argus display 
great skill and precision in slipping into their nest, the former 
actually diving into her open door-way without stopping at the en- 
trance. 

The manner of entering the nest depends somewhat on whether 
the nest is open or closed when the wasp arrives. In this particular 
there is great variation in the species as well as in the individuals. 
Microbembex usually closes her nest on leaving it but sometimes 
leaves it open; with Bembex texanus the exact opposite habit 
prevails. Ammophila Procera closes her nest after each visit in 
cases where she stores more than one caterpillar. Monedula caro- 
lina leaves her nest open as often as she closes it, Bembex belfraegu 
and Bembidula close their nest more often than they leave it open. 
Miscophus and Hoplisoides always carefully close their nests be- 
fore leaving. Thyreopus, Alyson and all solitary wasps that use 
mud in their architecture never close their nests on leaving on a 
hunting expedition; the female Trypoxylon, however, leaves the 
male on guard in her absence. Among the spider-ravishers that 
capture their prey before digging their nests many carry their spi- 
der out of reach of predatory enemies until the nest is ready 
(Fig. 5). 

A given species of wasp will usually confine herself to a particular 
kind of prey: a bug-catcher will always take bugs, a spider-ravisher 
never anything but spiders, an Ammophila only caterpillars, ete. 
Sometimes, as in the case of Priononyx Thomae, Alysonmelleus 
and Rhopalum abdominale and Thryeopus argus, the specialization 
is so complete that a certain species of grasshopper, leaf-hopper 
or fly is adhered to, all other grasshoppers, leafhoppers or flies being 
refused. The opposite habit, a universality of insect-food, obtains 
with Microbembex, which carries to her young any insect dead or 
alive or any part of an insect which she can find and capture 
(Chap. III.) 

Each species of wasp has learned the life habits of its prey and 
therefore frequents the latter’s haunts. Bembea texanus and other 
fly-catchers hover around the droppings of cows and horses and 


70 Some Solitary Wasps of Texas. 


around these animals themselves ; Bembex belfraegi makes trees and 
bushes her hunting grounds; leaf-hopper catchers fly in and out 
among the grasses in search of food for their young; the cricket- 
killer Larra runs into and out of holes in the ground or under 
stones; Microbembex glides gracefully through the woods satisfied 
with the first insect or part of an insect that comes to view. 

As regards the feeding habits among solitary wasps two types may 
be recognized: first that in which the growing larva is fed by the 
mother from day to day until the larval or eating stage has passed 
and the larva has spun its cocoon and become quiescent; and sec- 
ond, the type in which the store of food is provided once for all, the 
egg laid among the provisions, the nest closed over the egg and the 
larva left to its fate. 

The Peckhams consider the habit of feeding the larva from day to 
day as the most primitive. They say: “It may be possible then that 
all wasps originally fed their young as Bembex now does and that 
while the instinct of storing the whole supply of food once for all 
was working itself out among solitary wasps, the instincts of life 
in a true society developed into those of our wasp communities.” 
From this point of view, Microbembex on the one hand and the 
social wasps on the other show the habit in its most primitive form 
since they not only feed their larvae until these pupate, but they 
gather almost any kind of insect food they find. The first step 
in the development among the Digger-wasps would then be the 
specialization shown in all other wasps of confining themselves to 
one kind of prey (flies, bugs, caterpillars, as the case may be). In 
this Bembex and some species of Monedula are most primitive, since 
they continue to feed their larvae from day to day. Finally comes 
the habit which obtains in nearly all solitary wasps of provisioning 
the nests once for all. This is shown in its highest form in the 
Ammophiles and Pompilides, which paralyze the caterpillars and 
spiders, store them in the nest and lay the egg upon them. In 
these cases the nest is closed long before the egg is hatched and the 
mother wasp never sees the larva. There are however, transitional 
cases between the habits of Bembex and that of Ammophila. Thus 
Monedula carolina, the big fly catcher, closes her nest several days 
before the larva spins its cocoon, after first supplying the larva with 
a sufficient supply of food. The little bug-catcher Bembidula parata 
shows a somewhat greater difference, for while she stores her nest as 
fast as she can with very small bugs, the work is not finished until 


Some Solitary Wasps of Texas. Fl 


the larva is at least half-grown. Another instance, showing a still 
greater step in the direction indicated, is shown by an Ammophala 
urnaria described by the Peckhams. ‘This species lays the egg on 
the first caterpillar brought in and stores the other or others as soon 
as she can. In one case, the mother wasp on her return with the 
second caterpillar found a larva a day old feasting on the caterpillar 
already provided. 

It is interesting to note that, parallel with the working out of 
the instinct to store the nest quickly and close it up over the un- 
hatched egg, runs the development of the stinging instinct, which 
aims to paralyze the prey to preserve it for the future offspring. 
Thus Microbembex, which is the most generalized in the mode of 
procuring food, seldom needs to sting her prey, for she nearly al- 
ways finds it dead. When she stings, it is to kill and from a single 
observation I judge her to be very awkward in the application of 
her sting. The five caterpillars I saw her carry into her nest were 
all dead. The greater part of the caterpillars captured by Ammo- 
phila or Odynerus, wasps that specialize in that kind of prey, are 
brought into the nest merely paralyzed instead-of killed outright. 

Bember tex and other fly-catchers sting their flies to death with 
a single prolonged sting as I observed in Chap. 1V. This suggests 
the idea that the primary purpose of the sting is to overcome the 
victim. 

Among most of the other solitary wasps the tendency to merely 
paralyze the victim is more or less perfectly developed. Bugs, 
grass-hoppers, bees, spiders or caterpillars are sometimes brought in 
stung to death, but often they live from a few days to many. The 
nearest approach to perfection is reached in the Ammophilae. So 
nearly perfect is the habit here that Fabre was led to assert that 
two conditions always obtain with Ammophila’s caterpillars and are 
absolutely essential to the perpetuity of the species: first, that the 
caterpillar must be sufficiently paralyzed to insure the safety of the 
egg, yet secondly, it must remain alive sufficiently long to furnish 
fresh food for the growing larva. Though Fabre has noted a 
slight variation in the number and order of the stings administered 
he insists of the necessity of stinging the caterpillar in the middle 
segments, one of which is to receive the egg, and his observations 
seem to bear him out. In Chap. II, I have given my own observa- 
tions on five caterpillars of Ammophila procera which fulfilled to a 
nicety the condition thus laid down by Fabre. In each case the 


72 Some Solitary Wasps of Tezas. 


caterpillar lived long after the egg should have hatched, yet in each 
case the caterpillar was sufficiently stung in the middle segments to 
insure the proper quiescence. It must be said, however, that the 
five caterpillars thus observed are not sufficient to yield conclusive 
results. In this connection we should listen to the Peckhams, whose 
opinions, diametrically opposed to those of Fabre on the question of 
the stinging and other instincts of wasps, yet seem to me to be well 
established. Fabre argues that the wasp’s actions are the result of 
an automatically perfect instinct which allows no variations. The 
Peckhams combat this view, holding that, in their study of wasps, 
the “one preeminent unmistakable and everpresent fact is variabil- 
ity ; variability in every particular; in the shape of a nest and in the 
manner of digging it, in the condition of the nest (whether closed 
or open) when left temporarily, in the method of stinging the prey, 
in the manner of carrying the victim, in the way of closing the nest 
and last, and most important of all, in the condition produced in the 
victims after stinging, some of them dying long before the larva is 
ready to begin on them, while others live long past the time at 
which they would be attacked and destroyed if we had not interfered 
with the natural course of events. And all this variability, we get 
from a study of nine wasps and fifteen caterpillars.” 

Fabre’s opinion of the instinct of wasps has long been the prevail- 
ing one among naturalists. Romanes depended on Fabre for his 
information. The question would not have been dreaded by Dar- 
win but welcomed with delight had he been aware of the facts as 
afterward presented by the Peckhams. The central point from 
which the influences of the older naturalists were drawn, was the 
assumption that the larvae must be nourished upon fresh food. 

The fact is now, however, fully established that the larva thrives 
quite as well upon dead as upon living food. , 

The study of the habits of animals is, indeed, a most fascinating 
branch of zoological work, and the solitary wasps, though so little 
studied, are among the most interesting objects of study owing to the 
great variety of their activities. As to the result to be derived from 
a study of their habits, the solitary wasps may be expected to con- 
tribute no small quota toward the solution of the psychological 
problems concerning the lower animals. 


LIST OF ILLUSTRATIONS. 


Pate I. 
Figures: 
1. Nest and Wasps, Polistes bellicosus; x 5-6. 
2. Bembex spinolae and Microbembex monodonta. Nat. size. 


3. Mud cells of Odynerus dorsalis; the open cell is being stored with 
caterpillars. Nat size. 

4. Same, next day; wasp in cell made afternoon before. Nat size. 

5. Spider placed on leaf by Pompilus marginatus for safe keeping. 


xl. 
6 Ammophila beginning her nest. Nat. size. 


PuaTeE II. 
7. Monedula carolina coming out of nest. Nat. size. 
8. Ammoplhila carrying chip of wood to throw into the nest on left 
of figure. <A little larger than nat. size. 

9. Caterpillar, prey of Ammophila, on left; full grown wasp grub and 
remnant of another caterpillar nearly devoured. About nat. 
size. 

10. Mud cells of Odynerus dorsalis ; open cell shows wasp grub eating 
on caterpillars. Nat size. 

11. Same, showing holes by which young wasps emerged. Nat. size. 

12. Prey of Pompilus marginatus removed from nest, showing  posi- 
tion of wasp’s egg. Nat. size. 

13. Ammophila at work; nest deepening; see Fig. 6. 

14. Bugs, prey of Bembesx belfraegi, showing egg of wasp. Nat. size. 


PLATE III. 
15. Cocoon of Monedula carolina surrounded by remains of flies de- 
voured by wasp larva. x%4. 
16. Ammophila carrying caterpillar. x 1] 1-3. 
17. Ammophila nests close together; nests of wasps No. 72 and No. 73. 
Nat. size. ; 
18. Nest of Ammophila, cross-section, showing debris in tunnel, cater- 
pillar in pocket and position of egg. One-half nat. size. 
19. Nest of Bembidula pictifrons, showing bugs in pocket. One-fourth 
nat. size. 
20. Prey of Agenia; spider with legs amputated and egg of wasp. 
Nat. size. 
21. Nest of Monedula carolina. One-fifth nat. size. 


PLatTe IV. 
22. Nest of Ammophila, showing excavated dirt at x 1-3 nat. size. 


23. Trypoaxylon texense, male and female, occupying deserted mud- 
dauber’s nest. Nat. size. 
24. Pit in ground showing wasp burrews. One-third nat. size. 


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TABLE OF CONTENTS. 


Page 

Ooegs VET RCET TEGO) mpi e ee Os as say SRR ts ieee ec Rr See a a ee 3 
l. Two Eumenidae. 

A. Odynerus dorsalis  -..-..-.---------2-------s----c-seecsneneeesneneteceeeeneeseces 

Bi Qdymerus ALVETSIS  <——--- —— anne seer en enna a sana een sees ecaneensemnnnennene 9 

II. Ammophila procera. .......-..--..------------------------ ee Po ee en Oe ll 

TIl. Bembex texanus and Microbembex monodonta....................-...------ 21 

1V. Some Fly-catchers. 
A. Monedula carolina, the Big Fly-catcher_-........ aE Se re 27 


B. Notes on the Stinging Habits of Tachysphox texanus, 
Bembex texanus and Notoglossa (Oxybelus americana 29 
V. The Bug-Hunters. 


A. Bembex belfraegi, the Big Bug-hunter......................-.---------- 52 

B. Bembidula parata and Bembidula pictifrons.................--.... 36 

C. Hoplisoides, sp? -.-....---------s----a----e-te-cecenesescerentnceceneenenetnenesenaness 39 

TOL GMI Sore seats Ce Seater eae eee eeeererce ectenc ie FEE oa tres ea 4] 

E. Rhopalum (Crabro) abdominale.........-....-----.---.--------------- 43 
VI. Agenia, the Amputator of Spider’s Legs. 

A. Agenia, sp. nov., and Agenia accepta, Two Diggers............ 45 


B. Agenia subcorticalis and Agenia mellipes, Two Architects 48 
VII. Some Other Spider-ravishers. 


A. Pompilus marginatus  --....--.----.--------:-----------n-neer ences 52 

B. Pompilogaster fuscipenmis  ....-..-..-----.-.--------------------c----eeee-enene= 54 

C. Pompilid That Does Not Bury lts Prey.........................-.-.-.- 54 

MP ME nsec Ue, SYN a cnn ncn ee sere ee 55 

VIII. Trypoxylon texense, a Pet of the Household.............--.--. 57 
IX. Some Enemies of the Orthoptera. 

Ae sbarrar americana amd. ber (Oricketse. 2.2. ccsccnemeccastvce-eeeeae= 61 

B. Prononys Thomac, a Locust-killer 72... 62 

X. Experiment on the Sense of Direction of Cerceris fumipennis.... 66 

Summary and Conclusions...........-..-----------------------------cescesseeneceeeeecenceeneneeeeee 67 


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es THE UNIVERSITY OF TE 
a oe s ‘MAIN UNIVERSITY, AUSTIN 
: MEDICAL DEPARTMENT, GALVESTON — 


ee Wey. L. Pratuze, LL.D. Paeamentes 


ako ‘dctiicatinnnl.” Tuition FREE. Aatrioalations fe 
eR - $30. 00 (Payable in Academic and Engineering Depart-_ 

~. ments in three annual installments). Annual expense 
$150.00 and upward. Proper credit for work in other ge sy 
Ba ge Nee stitutions. 


Rooke SUR oe, il oot MATIN. UNIVERSITY eet: 


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3 Veaietou opens October 2, 1905. tncaeahe vena rors a ‘ 
Reg equipped Libraries, Laboratories, Natural History and 
_ Geological Collections, Men’s and Women’s Dormitories. es 
af and Gymnasiums in Texas, Board at Cost. - ee sor Be) 5S 


Academic Department: courses of liberal study: ling ee 
to the degree of Bachelor of Arts, and courses. Jegee OS 
State Teachers’ Certificates. 2, 


Engineering Department: courses leading to aepnese ta 
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tig ne Law De artment: A three-year course leading to the — 
degree of Bachelor of Laws. Shorter special courses - ‘for. 
specially equipped students. 7 alan 


3 For further information and catalogue, address} 
Dies ee Oe Oe = WILSON WILLIAMS: Registrar, — ees 
eee Main University, Austin, TLexaies 2 es 
MEDICAL DEPARTMENT Je 


e Schools of Medicine, Pharmacy and Nursing. ‘Session: : 
of eight months begins October 5, 1905. Four-year graded | 
_-» course in Medicine; two-year courses in Pharmacy and © 34 
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home for women students of Medicine. — aes 
‘For further information and catalogue, address 
| Dr. W. S. Carter, Dean, 
Medical Pad pena = reg av Texas. s 


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